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GIFT   OF 
Prof.  R.   Tracy  Crawford 


LIBRARY 


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ASTRONOMY  LIBRARY 


x 


TJEANOaEAPHY 


A  BRIEF  DESCRIPTION   OF 


THE     CONSTELLATIONS     VISIBLE     IN     THE 
UNITED    STATES 


STAR-MAPS,   AND   LISTS   OF   OBJECTS   OBSERVABLE 
WITH   A   SMALL  TELESCOPE 


BY 

C.   A.   YOUNG,   PH.D.,  LL.D. 

LATE  PROFESSOR  OF  ASTRONOMY  IN  PRINCETON  UNIVERSITY 


A   SUPPLEMENT  TO    THE  AUTHOR'S  "ELEMENTS   OF  ASTRONOMY 
FOR  HIGH  SCHOOLS   AND  ACADEMIES" 


GINN  &  COMPANY 

BOSTON  •  NEW  YORK  •  CHICAGO  •  LONDON 


ASTRONOMY  UBRARtf 

ENTERED  AT  STATIONERS'  HALE 


COPYRIGHT,  1889  and  1897, 
BY  CHARLES  A.  YOUNG. 


ALL  RIGHTS  RESERVED. 


i 

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C,l\\    ,V    CoMTANV.   PKO- 

puiirroRS  •  BOSTON  •  U.S.A. 


ASTRONOMY 
;     LIBRARY 


PREFACE. 


THIS  brief  description  of  the  constellations  was  pre- 
pared, at  the  suggestion  of  a  number  of  teachers,  as  an 
integral  part  of  the  author's  "Elements  of  Astronomy." 
It  has  been  thought  best,  however,  for  various  reasons, 
to  put  it  into  such  a  form  that  it  can  be  issued  separately, 
and  used  if  desired  in  connection  with  the  larger  "Gen- 
eral Astronomy,"  or  with  any  other  text-book.  Since  the 
Uranography  also  has  to  be  used  more  or  less  in  the  open 
air  at  night,  many  will  probably  prefer  to  have  it  by  itself, 
so  that  its  use  need  not  involve  such  an  exposure  of  the 
rest  of  the  text-book.  All  references  marked  Astr.  are 
to  the  articles  of  the  "  Elements  of  Astronomy." 


M577114 


ALPHABETICAL    LIST    OF    THE    CONSTELLATIONS   DE- 
SCRIBED OR  MENTIONED  IN  THE  URANOGRAPHY. 


ABTICLK 

ARTICLE 

Andromeda 

16 

Hydra       . 

38 

Anser,  see  Vulpecula  . 

54 

Lacerta     . 

61 

Antinoiis,  see  Aquila  . 

56 

36 

Antlia 

45 

Leo  Minor 

37 

Aquarius    „ 

63 

Lepus 

27 

Aquila 

56 

Libra 

44 

Argo  Navis 

34 

Lupus 

45 

Aries 

19 

Lynx 

29 

Auriga 

22 

Lyra 

52 

Bootes 

42 

Mondceros 

32 

Camelopardus    . 

14 

Norma 

47 

35 

Ophiuchus 

.  48,  49 

Canes  Venatici  . 

41 

Orion 

.  24,  25 

Canis  Major 

33 

Pegasus      . 

62 

Canis  Minor 

31 

Perseus 

21 

Capricornus 

58 

Phoenix     . 

20 

Cassiopeia 

.    9,  10 

Pisces 

17 

Centaurus 

45 

Piscis  Austral  is. 

64 

Cepheus 

11 

(Pleiades) 

23 

Cetus 

20 

Sagitta 

55 

Coma  Berenicis 

40 

Sagittarius 

57 

Columba    . 

28 

Scorpio 

.  46,  47 

Corona  Borealis 

43 

Sculptor     . 

20 

Corvus 

38 

Serpens 

.  48,49 

Crater 

38 

Serpentarius,  see  Ophiuchus  48,  49 

Cygnus       .         .         . 

53 

Sextans 

37 

Delphlnus  . 

59 

Taurus 

23 

Draco 

.  12,  13 

Taurus  Poniatovii 

48 

Equiileus  . 

60 

Triangiilum 

18 

Eridanus    . 

26 

Ursa  Major 

.      5-7 

Gemini 

30 

Ursa  Minor 

8 

Grus 

64 

Virgo 

39 

Herciiles    . 

.  50,  51 

Vulpecula  . 

54 

471 


UKANOGRAPHY. 


THE   GEEEK   ALPHABET. 


Letters.         Name. 

Letters.        Name. 

Letters.        Name. 

A,  a,      Alpha. 

I,  e,        Iota. 

P,  p,  o,  liho. 

B,  ft      Beta. 

K,  K,      Kappa. 

25,  o-,  s,  Sigma. 

F,  y,      Gamma. 

A,  X,      Lambda. 

T,  T,       Tau. 

A    8,      Delta. 

M,  /*,      Mu. 

Y,  v,       Upsilon 

E,  e?      Epsilon. 

N,  v,      Nu. 

<S>,  <£,      Phi. 

Z,  £,      Zeta. 

W    ^          "Y"i 

a,  g,       AO. 

X,  x,      Chi. 

H,  77,      Eta. 

O,  o,       Omicron. 

*,  .A,     Psi. 

®,  (9,  .9,  Theta. 

n,  TT,     Pi. 

O,  co,      Omega, 

472 


UEANOGRAPHY, 


OR 

A  DESCRIPTION  OF  THE  CONSTELLATIONS. 

1.  A  general  knowledge  of  the  constellations  sufficient  to 
enable  one  to  recognize  readily  the  more  conspicuous  stars  and 
their  principal  configurations,  is  a  very  desirable  accomplish- 
ment, and  not  difficult  to  attain.     It  requires  of  course  the 
actual  study  of  the  sky  for  a  number  of  evenings  in  different 
parts  of  the  year;  and  the  study  of  the  sky  itself  must  be 
supplemented  by  continual  reference  to  a  celestial  globe  or 
star-map,  in  order  to  identify  the  stars  observed  and  fix  their 
designations.     A  well-made  globe  of  sufficient  size  is  the  best 
possible  help,  because  it  represents  things  wholly  without  dis- 
tortion, and  is  easily  " rectified"  (Astr.  528 J)  for  any  given 
hour,  so  that  the  stars  will  all  be  found  in  the  proper  quarter 
of  the  (artificial)  heavens,  and  in  their  true  relations.     But  a 
globe  is  clumsy,  inconvenient  out  of  doors,  and  liable  to  dam- 
age ;  and  a  good  star-map  properly  used  will  be  found  but 
little  inferior  in  efficiency,  and  much  more  manageable. 

2,  Star-Maps.  —  Such  maps  are  made  on  various  systems, 
each  presenting  its  own  advantages.     None  are  without  more 
or  less  distortion,  especially  near  the  margin,  though  they 

1  The  references  are  to  the  articles  in  the  Author's  "Elements  of  Astron- 
omy," to  which  this  Uranography  is  a  supplement. 

473 


8  TJRANOGRAPHY.  [§  2 

differ  greatly  in  this  respect.  In  all  of  them  the  heavens  are 
represented  as  seen  from  the  inside,  and  not  as  on  the  globe, 
which  represents  the  sky  as  if  seen  from  the  outside;  i.e.,  the 
top  of  the  map  is  north,  and  the  east  is  at  the  left  hand ;  so 
that  if  the  observer  faces  the  south  and  holds  up  the  map 
before  and  above  him,  the  constellations  which  are  near  the 
meridian  will  be  pretty  truly  represented. 

3.  We  give  a  series  of  four  small  maps  which,  though  hardly  on  a 
large  enough  scale  to  answer  as  a  satisfactory  celestial  atlas,  are  quite 
sufficient  to  enable  the  student  to  trace  out  the  constellations  and 
identify  the  principal  stars. 

In  the  map  of  the  north  circumpolar  regions  (Map  I.),  the  pole  is 
in  the  centre,  and  at  the  circumference  the  right-ascension  hours 
are  numbered  in  the  same  direction  as  the  figures  upon  a  watch 
face ;  but  with  24  hours  instead  of  12.  The  parallels  of  declination 
are  represented  by  equidistant  and  concentric  circles.  On  the  three 
other  rectangular  maps,  which  show  the  equatorial  belt  of  the  heavens 
lying  between  +  50°  and  —50°  of  declination,  the  parallels  of  declina- 
tion are  equidistant  horizontal  lines,  while  the  hour-circles  are  vertical 
lines  also  equidistant,  but  spaced  at  a  distance  which  is  correct  for 
declination  35°,  and  not  at  the  equator.  This  keeps  the  distortion 
within  reasonable  bounds  even  near  the  margin  of  the  map,  and 
makes  it  very  easy  to  lay  off  the  place  of  any  object  for  which  the 
right  ascension  and  declination  are  given. 

The  hours  of  right  ascension  are  indicated  on  the  central  hori- 
zontal line,  which  is  the  equator,  and  at  the  top  of  the  map  are  given 
the  names  of  the  months.  The  word  September,  for  instance,  means 
that  the  stars  which  are  directly  under  it  upon  the  map  will  be  near  the 
meridian  about  nine  o'clock  in  the  evening  during  that  month. 

4.  The  maps  show  all  the  stars  down  to  the  4£  magnitude  —  all 
that  are  easily  visible  on  a  moonlight  night.     A  few  smaller  stars  are 
also  inserted,  where  they  mark  some  peculiar  configuration  or  point 
out  some  interesting  telescopic  object.     So  far  as  practicable,  i.e.,  north 
of  —30°  Declination,  the  magnitudes  of  Pickering's  "Harvard  Pho- 
tometry" are  used.     The  places  of  the  stars  are  for  1900. 

474 


§  4]  THE    CIECUMPOLAR    CONSTELLATIONS.  9 

In  the  designation  of  clusters  and  nebulae  the  letter  M.  stands 
for  "Messier,"  who  made  the  first  catalogue  of  103  such  objects  in 
1784  ;  e.g.,  97  M.  designates  No.  97  on  that  list.  A  few  objects  from 
Herschel's  catalogue  are  denoted  by  $  with  a  number  following. 

The  student  or  teacher  who  possesses  a  telescope  is  strongly  urged 
to  get  Webb's  "Celestial  Objects  for  Common  Telescopes."  It  is 
an  invaluable  accessory.  (Longmans,  Green  &  Co.,  N.  Y.) 

THE   CIRCUMPOLAR   CONSTELLATIONS. 

We  begin  our  study  of  Uranography  with  the  constellations 
which  are  circumpolar  (i.e.,  within  40°  of  the  north  pole), 
because  these  are  always  visible  in  the  United  States,  and  so 
can  be  depended  on  to  furnish  land  (or  rather  sky)  -marks  to 
aid  in  identifying  and  tracing  out  the  others. 

5.  Ursa  Major,  the  Great  Bear  (Map  I.).  — Of  these  cir- 
cumpolar constellations  none  is  more  easily  recognizable  than 
Ursa  Major.     Assuming  the  time  of  observation  as  about  eight 
o'clock  in  the  evening  on  Sept.  22d  (i.e.,  20h  sidereal  time), 
it  will  be  found  below  the  pole  and  to  the  west.     Hold  the 
map  so  that  the  VIII.  is  at  the  bottom,  and  it  will  be  rightly 
placed  for  the  time  assumed. 

The  familiar  Dipper  is  sloping  downward  in  the  northwest, 
composed  of  seven  stars,  all  of  about  the  second  magnitude  ex- 
cepting 8  (at  the  junction  of  the  handle  to  the  bowl),  which  is 
of  the  third.  The  stars  a  and  fi  are  known  as  the  "  Pointers," 
because  the  line  drawn  from  ft  through  a,  and  produced  about 
30°,  passes  very  near  the  Pole-star. 

The  dimensions  of  the  Dipper  furnish  a  convenient  scale  of 
angular  measure.  From  a  to  ft  is  5°;  a  to  8  is  10° ;  (3  to  y,  8°  j 
from  a  to  77  at  the  extremity  of  the  Dipper-handle  (which  is  also 
the  Bear's  tail)  is  26°. 

6.  The  Dipper  (known  also  in  England  as  the  "Plough," 
and  as  the  "Wain,"  or  wagon)  comprises  but  a  small  part  of 

475 


10  URANOGRAPHY.  L§  ti 

the  whole  constellation.  The  head  of  the  Bear,  indicated  by 
a  scattered  group  of  small  stars,  is  nearly  on  the  line  from  8 
through  a,  carried  on  about  15° ;  at  the  time  assumed  (2()h  sid. 
time),  it  is  almost  exactly  below  the  pole.  Three  of  the  four 
paws  are  marked  each  by  a  pair  of  third  or  fourth  magnitude 
stars  11°  or  2°  apart.  The  three  pairs  are  nearly  equidistant, 
about  20°  apart,  and  almost  on  a  straight  line  parallel  to  the 
diagonal  of  the  Dipper-bowl  from  a  to  y,  but  some  20°  south  of 
it.  Just  now  (20h  sid.  time)  they  are  all  three  very  near  the 
horizon  for  an  observer  in  latitude  40°,  but  during  the  spring 
and  summer  they  can  be  easily  made  out. 

7.   Names1  of  Principal  Stars. — 

a.  DUBHE.  e.  ALIOTH. 

ft.  MEKAK.  £.  MIZAR.     The  little  star  near  it  is 

y.  Phecda.  Alcor,  the  "rider  on  his  horse." 

8.  Megrez.  rj.  BENETNASCH  or  Alkaid. 

Doulle  Stars:  (1)  £  (Mizar),  Mags.  3  and  5;  Pos.2  140°;  Dist. 
14".5.  In  looking  at  this  object  the  tyro  will  be  apt  to  think  that  the 
small  star  shown  by  the  telescope  is  identical  with  Alcor :  a  very  low 
power  eye-piece  will  correct  the  error.  (Astr.  Fig.  113.)  The  large 
star  is  itself  a  "  spectroscopic  binary  "  (see  Art.  465*).  (2)  £,  the 
southern  one  of  the  pair  which  marks  the  left  hind  paw.  Binary: 
Mags.  4  and  5;  Pos.  (1910)  (about)  120°,  Dist.  (about)  3".  Position 
and  distance  both  change  rapidly,  the  period  being  only  61  years. 
This  was  the  first  binary  whose  orbit  was  computed. 

Clusters  and  Nebulae:  (1)  81  and  82  M.,  A.R.  9h  45m,  Dec.  69° 44'. 
Two  nebulae,  one  pretty  bright,  about  half  a  degree  apart.  (2)  97  M., 
A.R.  llh  07m,  Dec.  55°  43' — 2°  south-following  ft.  A  planetary  nebula. 

1  Capitals  denote  names  that  are  generally  used ;  the  others  are  met  with 
only  rarely. 

2 The  "  position  angle"  of  a  double  star  is  the  angle  which  the  line  drawn 
from  the  larger  star  to  the  smaller  one  makes  with  the  hour-circle.  It  is 
always  reckoned  from  the  north  completely  around  through  the  east,  as 
shown  in  Fig.  A. 

476 


URSA  MINOR,   THE  LESSER  BEAR. 


11 


8.  Ursa  Minor,  the  Lesser  Bear  (Map  I.).  —  The  line  of  the 
"Pointers"  unmistakably  marks  out  the  Pole-star  ("Polaris" 
or  "Cynosura"),  a  star  of  the  second  magnitude  standing  alone. 
It  is  at  the  end  of  the  tail  of  Ursa  Minor,  or  at  the  extremity 
of  the  handle  of  the  "  Little  Dipper,"  for  in  Ursa  Minor,  also, 
the  seven  principal  stars  form  a  dipper,  though  with  the  handle 
bent  in  a  different 

way  from  that  of 
the  other  Dipper. 
Beginning  at  "Po- 
laris "  a  curved  line 
(concave  towards 
Ursa  Major)  drawn 
through  8  and  e 
brings  us  to  £,  where 
the  handle  joins  the 
bowl.  Two  bright 
stars  (second  and 
third  magnitude),  /3 
and  y,  correspond  to 
the  pointers  in  the 
larger  Dipper,  and 
are  known  as  the 
"Guardians  of  the 
Pole":  13  is  called 

"Kochab"     The  remaining  corner  of  the  bowl  is  marked  by 
the  faint  star  rj  with  another  still  smaller  one  near  it. 

The  Pole  lies  about  1  J°  from  the  Pole-star,  on  the  line  joining 
it  to  £  Ursse  Major  is  (at  the  bend  in  the  handle  of  the  large 
Dipper). 

Telescopic  Object.  Polaris  has  a  companion  of  the  9|  magnitude, 
distant  18".6,  —  visible  with  a  two-inch  telescope. 

9.  Cassiopeia   (Map  I.).  —  This    constellation  lies   on   the 
opposite  side  of  the  pole  from  the  Dipper  at  about  the  same 

477 


FIG.  A.  —  Measurement  of  Distance  and  Position- Angle 
of  a  Double  Star. 


12  URAttOGRAPHV.  [§  ^ 

distance  as  the  "Pointers,"  and  is  easily  recognized  by  the 
zigzag,  "  rail-fence  "  configuration  of  the  five  or  six  bright  stars 
that  mark  it.  With  the  help  of  the  rather  inconspicuous  star 
K,  one  can  make  out  of  them  a  pretty  good  chair  with  the  feet 
turned  away  from  the  pole.  But  this  is  wrong.  In  the  recog- 
nized figures  of  the  constellation  the  lady  sits  with  feet  towards 
the  pole,  and  the  bright  star  a  is  in  her  bosom,  while  £  and  the 
other  faint  stars  south  of  a,  are  in  her  head  and  uplifted  arms : 
i,  on  the  line  from  8  to  e  produced,  is  in  the  foot.  The  order 
of  the  principal  stars  is  easily  remembered  by  the  word  Bagdei; 
i.e.,  ft,  a,  y,  8,  e,  t. 

Names  of  Stars :  a  (which  is  slightly  variable)  is  known  as  SCHEDIR  ; 
ft  is  called  CAPH. 

Double  Stars:  (1)  rj,  Mags.  4-7 £.  Large  star  orange;  small  one 
purple.  Pos.  170°  ±,  Dist.  5".5.  Binary,  with  a  period  of  some  200 
years.  Easily  recognized  by  its  position  about  half-way  between  a 
and  y,  a  little  off  the  line.  (2)  ^,  A.R.  lh  17m,  Dec.  67°  21' ;  Triple ; 
Mags.  4i,  9  and  9;  Pos.  A  to  (B  +  C)  106°,  Dist.  29";  Pos.  B-C  257°, 
Dist.  2". 9.  Found  on  a  line  from  rj  through  y  produced  three  times 
the  distance  rj-y:  rather  difficult  for  a  four-inch  telescope. 

10.  The  Sidereal  Time  determined  by  the  Apparent  Position 
of  Cassiopeia.  —  The  line  from  the  Pole-star  through  Caph  or  ft 
Cassiopeiae  (which  is  the  leader  of  all  the  bright  stars  of  the  constella- 
tion in  their  daily  motion)  is  almost  exactly  parallel  to  the  Equinoc- 
tial Colure.     When,  therefore,  this  star  is  vertically  above  the  Pole-star 
it  is  sidereal  noon;  it  is  6h  when  it  is  on  the  great  circle  (not  the  par- 
allel of  altitude)  drawn  from  the  Pole-star  to  the  west  point  of  the 
Horizon ;   12h  when  vertically  below  it ;  and  18h  when  due  east.     A 
little  practice  will  enable  one  to  read  the  sidereal  time  from  this  celes- 
tial clock  with  an  error  not  exceeding  15  or  20  minutes. 

11.  Cepheus  (Map  L).  —  This  constellation  contains  very 
few  bright  stars.     At  the  assumed  time  (20h  sidereal)  it  is 
above  and  west  of  Cassiopeia,  not  having  quite  reached  the 
meridian  above  the  pole.     A  line  carried  from  a  Cassiopeia 
through  /?,  and  produced  20°  (distance  a  .  .  .  £  =  5°  nearly) 

478 


§  11]  DRACO.  13 

will  pass  very  near  to  a  Cephei,  a  star  of  the  third  magnitude, 
in  the  king's  right  shoulder,  ft  Cephei  is  about  8°  due  north  of 
a,  and  y  about  12°  from  ft,  both  also  of  third  magnitude :  y  is  so 
placed  that  it  is  at  the  obtuse  angle  of  a  rather  flat  isosceles 
triangle  of  which  ft  Cephei  and  the  Pole-star  form  the  two  other 
corners.  Cepheus  is  represented  as  sitting  behind  Cassiopeia 
(his  wife)  with  his  feet  upon  the  tail  of  the  Little  Bear,  y  being 
in  his  left  knee.  His  head  is  marked  by  a  little  triangle  of 
fourth  magnitude  stars,  8,  e,  and  £,  of  which  8  is  a  remarkable 
variable  with  a  period  of  5J  days  (see  Astr.  Table  IV.). 
There  are  several  other  small  variables  in  the  same  neighbor- 
hood,, but  none  of  them  are  shown  on  the  map. 

Names  of  Stars:  a  is  Alderamin,  and  ft  is  Alphirk. 

Double  Stars:  (1)  ft,  Mags.  3  and  8;  Pos.  251°;  Dist.  14".  (2)  8, 
Mags,  larger  star  3.7  to  5  (variable),  smaller  one  7;  Pos.  192°,  Dist. 
41" ;  Colors,  yellow  and  blue.  (3)  *,  A.R.  20h  13%  Dec.  77°  19' ;  Mags. 
4.5  and  8.5;  Pos.  124°;  Dist.  7."5;  Colors,  yellow  and  blue. 

12.  Draco  (Map  I.).  —  The  constellation  of  Draco  is  char- 
acterized by  a  long,  sinuous  line  of  stars,  mostly  small,  extend- 
ing half-way  around  the  pole  and  separating  the  two  Bears. 
A  line  from  8  Cassiopeise  drawn  through  ft  Cephei  and  ex- 
tended about  as  far  again  will  fall  upon  the  head  of  Draco, 
marked  by  an  irregular  quadrilateral  of  stars,  two  of  which 
are  of  the  2J  and  3d  magnitude.  These  two  bright  stars  about 
4°  apart  are  ft  and  y ;  the  latter  in  its  daily  revolution  passes 
almost  exactly  through  the  zenith  of  Greenwich,  and  it  was  by 
observations  upon  it  that  the  aberration  of  light  was  discovered 
(Astr.  125).  The  nose  of  Draco  is  marked  by  a  smaller  star,  /*, 
some  5°  beyond  ft,  nearly  on  the  line  drawn  through  it  from  y. 
From  y  we  trace  the  neck  of  Draco,  eastward  and  downward ! 
towards  the  Pole-star  until  we  come  to  8  and  €  and  some  smaller 
stars  near  them.  There  the  direction  of  the  line  is  reversed, 

1The  description  here  applies  strictly  only  at  20h  sid.  time. 
479 


14  URANOGRAPHY.  [§  12 

so  that  the  body  of  the  monster  lies  between  its  own  head  and 
the  bowl  of  the  Little  Dipper,  and  winds  around  this  bowl  until 
the  tip  of  the  creature's  tail  is  reached  at  the  middle  of  the 
line  between  the  Pointers  and  the  Pole-star.  The  constella- 
tion covers  more  than  12h  of  right  ascension. 

13.  One   star  deserves   special  notice :   a,  a  star  of  the  3J 
magnitude  which  lies  half-way  between  Mizar  (£  Urs.  Maj.) 
and  the  Guards  (/?  and  y  Urs.  Min.)  ;   4700  years  ago  it  was 
the  Pole-star,  within  10'  or  15'  of  the  pole,  and  much  nearer 
than  Polaris  is  at  present,  or  ever  will  be.     It   is   probable 
that  its  brightness   has   considerably  diminished  within   the 
last  200  years ;  since  among  the  ancient  and  mediaeval  astron- 
omers it  was  always  reckoned  of  the  second  magnitude. 

Names  of  Stars:  a.  is  THUBAN;  ft,  Alwaid ;  and  y,  Etanin. 

Double  Stars:  (1)  p,  Mags.  4  and  4^ -;  Pos.  165°;  Dist.  2".5.  Bi- 
nary, with  a  probable  period  of  about  600  years.  (2)  e,  Mags.  4, 
8;  Pos.  0°.0;  Dist.  2".9;  yellow  and  blue.  Nebula,  A.R.  17h  59m; 
Dec.  66°  38  .  Planetary,  like  a  star  out  of  focus.  This  object  is 
almost  exactly  at  the  pole  of  the  ecliptic,  about  midway  between  8  and 
£  Draconis,  but  a  little  nearer  £. 

14.  Camelopardus  (Map  I.).  —  This  is  the  only  remaining  one 
of  the  strictly  circumpolar  constellations  —  a  modern  asterism  contain- 
ing no  stars  above  fourth  magnitude,  and  constituted  by  Hevelius 
simply  to  cover  the  great  empty  space  between  Cassiopeia  and  Perseus 
on  one  side,  and  Ursa  Major  and  Draco  on  the  other.     The  animal 
stands  on  the  head  and  shoulders  of  Auriga,  and  his  head  is  between 
the  Pole-star  and  the  tip  of  the  tail  of  Draco. 

The  two  constellations  of  Perseus  (which  at  20b  sidereal  time  is 
some  20°  below  Cassiopeia)  and  of  Auriga  are  partly  circumpolar,  but 
on  the  whole  can  be  more  conveniently  treated  in  connection  with  the 
equatorial  maps.  Capella,  the  brightest  star  of  Auriga,  and  next  to 
Vega  and  Arcturus  the  brightest  star  in  the  northern  hemisphere,  at 
the  time  assumed  (Sept.  22,  8  P.M.),  is  a  few  degrees  above  the  horizon 
in  the  N.E.  Between  it  and  the  nose  of  Ursa  Major  is  part  of  the 
constellation  of  the  Lynx,  —  a  modern  asterism  made,  like  Camelopar- 
dus, merely  to  fill  a  gap. 

480 


§  15]  MILKY  WAY   IN   CIRCUMPOLAR  REGION.  15 

15.  Tlie  Milky  Way  in  the  Circumpolar  Region.  — The  only 
circumpolar  constellations  traversed  by  it  are  Cassiopeia  and 
Cepheus.  It  enters  the  circumpolar  region  from  the  constella- 
tion of  Cygnus,  which  at  20h  sidereal  time  is  just  in  the  zenith, 
sweeps  down  across  the  head  and  shoulders  of  Cepheus,  and 
on  through  Cassiopeia  and  Perseus  to  the  northeastern  horizon 
in  Auriga.  There  is  one  very  bright  patch  a  degree  or  two 
north  of  /?  Cassiopeise ;  and  half-way  between  Cassiopeia  and 
Perseus  there  is  another  bright  cloud  in  which  is  the  famous 
cluster  of  the  "Sword  Handle  of  Perseus"  — a  beautiful  object 
for  even  the  smallest  telescope. 


16.  Andromeda  (Map  II.). — Passing  now  to  the  equato- 
rial maps  and  beginning  with  the  northwestern  corner  of  Map 
N"o.  II.,  we  come  first  to  the  constellation  of  Andromeda,  which 
will  be  found  exactly  overhead  in  our  latitudes  about  10  o'clock 
in  the  middle  of  November,  or  at  8  o'clock  a  month  later.  Its 
characteristic  configuration  is  the  line  of  three  second-magni- 
tude stars,  a,  13,  and  y,  extending  east  and  north  from  a,  which 
itself  forms  the  N.E.  corner  of  the  so-called  u  Great  Square  of 
Pegasus,"  and  is  sometimes  lettered  as  8  Pegasi.  This  star 
may  readily  be  found  by  extending  an  imaginary  line  from 
Polaris  through  ft  Cassiopeise,  and  producing  it  about  as  far 
again :  a  is  in  the  head  of  Andromeda,  ft  in  her  waist,  and  y 
in  the  left  foot.  About  half-way  from  a  to  /?,  a  little  south 
of  the  line,  is  8  (of  the  third  magnitude)  with  TT  and  c  of  the 
fourth  magnitude  near  it.  A  line  drawn  northwesterly  from 
J3  nearly  at  right  angles  to  the  line  /?y,  will  pass  through  ^  at 
a  distance  of  about  5°,  and  produced  another  5°  will  strike 
the  "great  nebula"  (Astr.  470),  which  forms  a  little  obtuse- 
angled  triangle  with  v  and  a  sixth-magnitude  star  known  as 
32  Andromedse. 

Andromeda  has  her  mother,  Cassiopeia,  close  by  on  the  north,  and 
at  her  feet  is  Perseus,  her  deliverer,  while  her  Viead  rests  upon  the 

481 


16  URANOGEAPHY.  [§  16 

shoulder  of  Pegasus,  the  winged  horse  which  brought  Perseus  to  her 
rescue.  To  the  south,  beyond  the  intervening  constellations  of  Aries 
and  Pisces,  Cetus,  the  sea-monster,  who  was  to  have  devoured  her, 
stretches  his  ungainly  bulk. 

Names  of  Stars,     a,  AlpJieratz  ;  ft,  Mirach;  y,  Almaach. 

Double  Stars.  (1)  y,  Mags.  3,  5;  Pos.  62°;  Dist.  11";  colors, 
orange  and  greenish  blue  —  a  beautiful  object.  The  small  star  is 
itself  double,  but  at  present  so  close  as  to  be  beyond  the  reach  of  any 
but  very  large  instruments  (Astr.  Fig.  113).  (2)  TT  (2°  N".  and  a 
little  west  of  8),  Mags.  4,  9 ;  Pos.  174°;  Dist.  36";  white  and  blue. 

Nebulce.  M.  31;  the  great  nebula;  visible  to  naked  eye.  M.  32; 
small,  round,  and  bright,  is  in  the  same  low-power  field  with  31; 
south  and  east  of  it. 

17.  Pisces  (Map  II.).  —  Immediately  south,  of  Andromeda 
lies  Pisces,  the  first  of  the  zodiacal  constellations,  though  now 
occupying  (in  consequence  of  precession)  the  sign  of  Aries. 
It  has  not  a  single  conspicuous  star,  and  is  notable  only  as  con- 
taining the  vernal  equinox,  or  first  of  Aries,  which  lies  near 
the  southern  boundary  of  the  constellation  in  a  peculiarly  star- 
less region.     A  line  from  a  Andromedse  through  y  Pegasi  con- 
tinued as  far  again  strikes  about  2°  east  of  the  equinox. 

The  body  of  the  southern  fish  lies  about  15°  south  of  the  middle  of 
the  southern  side  of  the  great  square  of  Pegasus,  and  is  marked  by  an 
irregular  polygon  of  small  stars,  5°  or  6°  in  diameter.  A  long  crooked 
"  ribbon  "  of  little  stars  runs  eastward  for  more  than  30°,  terminating 
in  a  Piscium,  called  El  Rischa,  a  star  of  the  fourth  magnitude  20° 
south  of  the  head  of  Aries.  From  there  another  line  of  stars  leads  up 
N.W.  in  the  direction  of  8  Andromedse  to  the  northern  fish,  which  lies 
in  the  vacant  space  south  of  ft  Andromedse. 

Double  Stars.  (1)  a,  Mags.  4,  5.5;  Pos.  324°;  Dist.  3".  (2) 
$'  (2°  S.E.  of  rj  Andromedse  —  see  map),  Mags.  4.9,  5;  Pos.  160°; 
Dist.  31". 

18.  Triangulum  (Map  Tl.).  —  This  little  constellation,  insignifi- 
cant as  it  is,  is  one  of  Ptolemy's  ancient  48.      It  lies  half-way  be- 
tween y  Andromedae  and  the  head  of  Aries,  characterized  by  three 
stars  of  the  third  and  fourth  magnitudes. 

482 


§  18]  ABIES.  17 

Double  Stars.  (1)  i  or  6  (5°  nearly  due  south  of  ft  Trianguli,  and 
at  the  obtuse  angle  of  an  isosceles  triangle  of  which  a  and  y  are  the 
other  two  corners),  Mags.  5,  6.5;  Pos.  76°;  Dist.  4";  topaz-yellow 
and  green. 

19.  Aries  (Map  II.).  —  This  is  the  second  of  the  zodiacal 
constellations  (now  occupying  the  sign  of  Taurus).  It  is  bounded 
north  by  Triangulum  and  Perseus,  west  by  Pisces,  south  by 
Cetus,  and  east  by  Taurus.     The  characteristic  star-group  is 
that  composed  of  a,  /?.  y  (see  map),  about  20°  due  south  of  y 
Andromedse :  a,  a  star  of  the  2i-  magnitude  is  fairly  conspicu- 
ous, forming  as  it  does  a  large  isosceles  triangle  with  /?  and  y 
Andromedse. 

Names  of  Stars,     a,  Hamal ;  (3,  Sheratan;  y,  Mesartim. 

Double  Stars.  (1)  y,  Mags.  4.5,  5;  Pos.  0°;  Dist.  8".8.  (This  is 
probably  the  earliest  known  double  star;  noticed  by  Hooke  in  1664.) 
(2)  e,  Mags.  5,  6.5;  Pos.  200°;  Dist.  1  ".2.  (About  one-third  of  the 
way  from  a  Arietis  towards  Aldebaran,  £  is  4°  beyond  it  on  the  same 
line.)  This  is  probably  too  difficult  for  any  instrument  less  than  4  or 
4.t  inches'  aperture.  (3^  TT,  Triple;  Mags.  5,  8.5,  and  11;  A-B,  Pos. 
122°;  Dist.  3".l ;  A-C,  Pos.  110°;  Dist.  25".  (At  the  southern  corner 
of  a  nearly  isosceles  triangle  formed  with  e  and  r,  e  being  at  the  obtuse 
angle.) 

The  star  41  Arietis  (3.^  mag.),  which  forms  a  nearly  equilateral  tri- 
angle with  a  Arietis  and  y  Trianguli,  constitutes,  with  two  or  three 
other  small  stars  near  it,  the  constellation  of  Musca  (Borealis),  a  con 
stellation,  however,  not  now  generally  recognized. 

20.  Cetus  (Map  II.).  —  South  of  Aries  and  Pisces  lies  the 
huge  constellation  of  Cetus,  which  backs  up  into  the  sky  from 
the  southeastern  horizon.     The  head  lies  some  20°  S.E.  of  a 
Arietis,  marked  by  an  irregular  pentagon  of  stars,  each  side  of 
which  is  5°  or  6°  long.     The  southern  edge  of  it  is  formed  by 
the  stars  a  (2^  mag.)  and  y  (3J-  mag.)  :  8  lies  nearly  south  of 
y.     /?,  the  brightest  star  of  the  constellation  (2d  magnitude), 
stands  alone  nearly  40°  west  and  south  of  a.     About  half-way 

483 


18  TTRAKOGRAPHY.  l§  20 

from  ft  to  y  the  line  joining  them  passes  through  a  character- 
istic quadrilateral  (see  map),  the  N.E.  corner  of  which  is  com- 
posed o£  two  fourth-magnitude  stars,  £  and  x-  The  remarkable 
variable  o  Ceti  (Mira)  lies  almost  exactly  on  the  line  joining 
y  and  £,  a  little  nearer  to  y  than  to  £.  It  is  visible  to  the  naked 
eye  for  about  a  month  or  six  weeks  every  eleven  months, 
when  near  its  maximum. 

Names  of  Stars,  a,  MENKAR  ;  ft,  Diphda  or  Deneb  Kaitos  ;  £,  Eaten 
Kaitos ;  o,  MIRA. 

Double  Stars.  (1)  y,  Mags.  3.5,7;  Pos.  290°;  Dist.  2".5;  yellow 
and  blue. 

South  of  Cetus  lies  the  constellation  of  Sculptoris  Apparatus  (usu- 
ally known  simply  as  Sculptor),  which,  however,  contains  nothing 
that  requires  notice  here.  South  of  Sculptor,  and  close  to  the  horizon, 
even  when  on  the  meridian,  is  Phoenix.  It  has  some  bright  stars, 
but  none  easily  observable  in  the  United  States. 

21.  Perseus  (Maps  I.  and  II.). —  Returning  now  to  the 
northern  limit  of  the  map,  we  come  to  the  constellation  of 
Perseus.  Its  principal  star  is  a,  rather  brighter  than  the 
standard  second  magnitude,  situated  very  nearly  on  the  pro- 
longation of  the  line  of  the  three  chief  stars  of  Andromeda. 
A  very  characteristic  configuration  is  "the  segment  of  Per- 
seus'7 (Map  I.),  a  curved  line,  formed  by  8,  a,  y,  and  vj,  with 
some  smaller  stars,  concave  towards  the  northeast,  and  run- 
ning along  the  line  of  the  Milky  Way  towards  Cassiopeia. 
The  remarkable  variable  star  ft,  or  Algol  (Astr.  453),  is  situ- 
ated about  9°  south  and  a  little  west  of  a,  at  the  right  angle 
of  a  right-angled  triangle  which  it  forms  with  a  (Persei)  and 
y  Andromedse.  Some  8°  south  and  slightly  east  of  8  is  e,  and 
8°  south  of  e  are  £  and  o  of  the  fourth  magnitude  in  the  foot  of 
the  hero.  Algol  and  a  few  small  stars  near  it  form  "  Medusa's 
Head." 

Names  of  Stars,     a  is  Marfak,  or  ALGENIB;  ft  is  ALGOL. 
Double  Stars.     (1)    c,  Mags.  3.5,  0;    Pos.  10°;    Dist.  8".4.     (2)  & 

484 


§  21]  AUKIGA.  19 

Quadruple;  Mags.  3.5,  10,  11,  12;  Pos.  A-B,  207°;  Dist.  13".2,  83", 
121".     (3)  77,  Mags.  5,  8.5;  Pos.  300°;  Dist.  28";  orange  and  blue. 

Clusters.  (1)  $  VI.  33  and  34.  Magnificent.  Half-way  between 
y  Persei  and  8  Cassiopeise.  (2)  M.  34;  A.  11.  2"  34- ;  Dec.  42°  11'; 
coarse,  with  a  pretty  double  star  (eighth  mag.)  included. 

22.  Auriga  (Maps  I.  and  II.).  —  Proceeding  east  from  Per- 
seus we  come  to  Auriga,  instantly  recognized  by  the  bright 
yellow  star  CAPELLA  (the  Goat)  and  her  attendant  Hoedi  (or 
Kids).     Capella,  a  Aurigse,  according  to  Pickering,  is  precisely 
of  the  same  brightness  as  Vega  (Mag.  =  0.2),  both  of  them 
being  about  J  of  a  magnitude  fainter  than  Arcturus,  but  dis- 
tinctly brighter  than  any  other  stars  visible  in  our  latitudes 
except  Sirius  itself.     About  10°  east  of  Capella  is  (3  Aurigae 
of 'the  second  magnitude,  and  8°  south  of  ft  is  0  of  the  third 
magnitude;    8  Aurigye  is  10°  north  of  ft  in  the  circumpolar 
region,    e,  £,  and  77,  4°  or  5°  S.W.  of  a,  are  the  "Kids." 

Names  of  Stars,     a,  CAPELLA  ;  (3,  MENKALINAN. 

Double  Stars.  (1)  <o,  Mags.  5,  9;  Pos.  353°;  Dist.  7";  white,  light 
blue.  ft  is  a  spectroscopic  double  (see  Art.  465*). 

Clusters.  (1)  M.  37;  A.R.  5h  44m ;  Dec.  32°  31'  (on  the  line 
from  0  Aurigse  to  £  Tauri,  one-third  of  the  way  from  0).  Fine  for 
small  instrument.  (2)  M.  38;  A.R.  5h  21m ;  Dec.  35°  47'.  Nearly 
at  the  middle  of  the  line  from  0  to  w.  (3)  M.  30 ;  A.R.  5h  28m;  Dec. 
34°  3'.  One-third  of  the  way  from  M.  38  to  M.  37. 

23.  Taurus  (Map  II.).  — This,  the  third  of  the  zodiacal 
constellations,  is  bounded  north  by  Perseus  and  Auriga,  west 
by  Aries,  south  by  Eridanus  and  Orion,  and  east  by  Orion  and 
Gemini.     It   is   unmistakably   characterized  by  the  Pleiades, 
and  by  the  V-shaped  group  of  the  Hyades  which  forms  the 
face  of  the  bull,  with  the  red  ALDEBARAN  (a  Tauri)  blazing  in 
the  creature's  eye,  as  he  charges  down  upon  Orion.    His  horns 
reach  out  towards  Gemini  and  Auriga,  and  are  tipped  with  the 
second  and  third  magnitude  stars  ft  and  £.     As  in  the  case  of 
Pegasus,  only  the  head  and  shoulders  appear  in  the  coiistella- 

4«5 


jf 


20  URANOGEAPHY.  C§  23 

tion.  Six  of  the  Pleiades  are  easily  visible,  and  on  a  dark  night 
a  fairly  good  eye  will  count  nine  (see  Astr.  469).  With  a 
3-inch  telescope  about  100  stars  are  visible  in  the  cluster.  In 
the  Hyades  the  pretty  naked-eye  double  01?  02,  is  worth  noting. 

Names  of  Stars,  a,  ALDEBARAN;  /?,  El  Nath ;  -q  (the  Jjrighte§J  of 
the  Pleiades),  ALCYONE.  For  the  names  of  the  other  Pleiades,  see  the 
figure  in  Art.  469  of  the  Astronomy. 

Double  Stars.  (1)  a  has  a  small,  distant  companion,  12th  magni- 
tude ;  Pos.  36° ;  Dist.  1'  48".  It  has  also  a  second  companion  much 
nearer  and  more  minute,  but  far  beyond  the  reach  of  ordinary  tele- 
scopes. (2)  T,  Mags.  5  and  8 ;  Pos.  210° ;  Dist.  62  ' ;  white  and  violet. 
Found  by  drawing  a  line  from  y  (at  the  point  of  the  V  oi  the  Hyades) 
through  e,  and  producing  it  as  far  again. 

Nebula.  M.  1;  A.R.  5h  27m;  Dec.  21°  56',  about  1°  west  and  a 
little  north  of  £.  Often  mistaken  for  a  comet.  The  so-called  "Crab 
Nebula." 

24.  Orioif^ot'  <5'-ri-on)  (Map  II.). — On  the  whole  this  is 
the  finest  constellation  in  the  heavens.  As  he  stands  facing 
the  bull  his  shoulders  are  marked  by  the  two  bright  stars,  a 
and  y,  the  former  of  which  in  color  and  brightness  closely 

atches  Aldebaran.  In  his  left  hand  he  holds  up  the  lion 
skin,  indicated  by  the  curved  line  of  little  stars  between  y  and 
the  Hyades.  The  top  of  the  club,  which  he  brandishes  in  his 
right  hand,  lies  between  £  Tauri  and  p  and  rj  Geminorum.  His 
head  is  marked  by  a  little  triangle  of  stars  of  which  A.  is  the 
chief.  IJi^JaeJJ^jjpjn^i^^  magni- 

tude pointing  obliquely  downward  towards  Sirius.  It  is  very 
nearly  3°  in  length,  with  the  stars  in  it  equidistant  like  a 
measuring-rod,  so  that  it  is  known  in  England  as  the  "Ell 
and  Yard."  From  the  belt  hangs  the  sword,  composed  of  three 
smaller  stars  lying  more  nearly  north  and  south :  the  middle 
one  of  them  is  the  multiple  0  in  the  great  nebula,  ft  Orionis, 
or  EJGEL,  a  magnificent  white  star,  is  in  the  left  foot,  and  K  is 
in  the  right  knee.  Orion  has  no  right  foot,  or  if  he  has,  it  is 

486 


§  243  ERIDANUS.  21 

hidden  behind  Lepus.  The  quadrilateral  a,  y,  8,  K,  with  the 
diagonal  belt  8,  e,  £,  once  learned  can  never  be  mistaken  for 
anything  else  in  the  heavens. 

25.  Names  of  Stars,    a,  BETELGEUSE;    ft,   RIGEL;    y,   Bellatrix; 
K,  Saiph ;  8,  Mintaka  ;  e,  Alnilam;  £,  Alnitak. 

Double  Stars.  In  these  Orion  is  remarkably  rich.  (1)  /3  (Rigel), 
Mags.  1  and  9;  Pos.  200°;  Dist.  9".5;  both  white,  —  a  beautiful  and 
easy  object.  (2)  8  (the  westernmost  star  in  the  belt),  Mags.  2.5  and 
7;  Pos.  0;  Dist.  53".  (3)  £,  Triple;  Mags.  2.5,  6.5,  10;  A-B,  Pos. 
155°,  Dist.  2".4;  A-C,  Pos.  9°,  Dist,  59".  (4)  i,  Triple;  Mags.  3.5,  8.5, 
11 ;  A-B,  Pos.  142°,  Dist.  11".5;  A-C,  Pos.  103°,  Dist.  49".  (This  is 
the  lowest  star  in  the  sword,  just  below  the  nebula.)  (5)  0,  Multiple, 
the  trapezium  in  the  nebula.  Four  stars  are  easily  seen  by  small 
telescopes  (Astr.  Fig.  113).  (6)  o-,  Triple;  Mags.  4,  8,  7  ;  A-B,  Pos. 
84°,  Dist.  12".5;  A-C,  Pos.  61°,  Dist.  42"  (1^°  S.W.  of  £). 

Nebula.  M.  42 ;  attached  to  the  multiple  star  0.  The  nebula  of  all 
the  heavens;  by  far  the  finest  known,  though  in  a  small  telescope 
wanting  much  of  the  beauty  brought  out  by  a  larger  one. 

26.  Eridanus  (Map  II.).  — This  constellation  lies  south  of 
Taurus,  in  the  space  between  Cetus  and  Orion,  and  extends  far 
below  the  southern  horizon.     Its  brightest  star  a  (ACHEKNAR) 
is  never  visible  in  the  United  States. 

Starting  with  (3  of  the  third  magnitude,  about  3°  north  and 
a  little  west  of  Eigel  (ft  Orionis),  one  can  follow  a  sinuous  line' 
of  stars,  some  of  them  of  the  third  and  fourth  magnitudes, 
westward  about  30°  to  the  paws  of  Cetus,  10°  south  of  a  Ceti  ; 
there  the  stream  turns  at  right  angles  southwards  for  10°,  then 
southeast  for  about  20°,  and  finally  southwestward  to  the  hori- 
zon. One  could  succeed  in  fully  tracing  it  out,  however,  only 
by  help  of  a  map  on  a  larger  scale  than  the  one  we  are  able 
to  present. 

Names  of  Stars,     ft,  Cursa ;  y,  Zaurack. 

Double  Stars.  (1)  32;  A.R.  3"  48%  Dec.  S.  3°  19';  Mags.  5,  7; 
Pos.  347°;  Dist.  6".6;  yellow,  blue;  very  fine.  (2)  o2,  Triple;  A.R. 

487 


22  UKANOGRAPHY.  [§  26 


4h  10m;  Dec.  S.  7°  50';  Mags.  5,  10,  10;  Pos.  A,  (^-±±J,  108°;  Dist. 
83";  Pos.  B-C,  110°,  Dist.  4";  very  pretty. 

27.  Lepus    (Map   II.).  —  This  little   constellation   (one    of    the 
ancient  48)  lies  just  south  of  Orion,  occupying  a  space  of  some  15° 
square.      Its  characteristic  configuration  is  a  quadrilateral  of  third 
and  fourth  magnitude  stars,  with  sides  from  3°  to  5°  long,  10°  south 
of  K  Orionis,  and  15°  west  and  a  little  south  of  Sirius. 

Double  Stars.  (1)  y  (the  S.E.  corner  of  the  quadrilateral)  is  a 
coarse  double.  Mags.  4,  6.5  ;  Pos.  350° ;  Dist.  93".  (2)  K  (5.]°  south 
of  Rigel),  Mags.  5  and  9  ;  Pos.  0°;  Dist.  3".7. 

28.  Columba  (Noah's  Dove)  (Map  II.).  — This  is  next  south  of 
Lepus  :  too  far  south  to  be  well  seen  in  the  Northern  States.    Its  prin- 
cipal star,  a,  or  Phact,  of  the  2£  magnitude,  is  readily  found  by  draw- 
ing a  line  from  Procyon  to  Sirius,  and  prolonging  it  nearly  the  same 
distance.    And  in  passing  we  may  note  that  a  similar  line  drawn  from 
a  Orionis  through  Sirius  and  produced,  will  strike  near  £  Argus,  or 
"  Naos,"  a  star  about  as  bright  as  Phact,  —  the  two  lines  which  inter- 
sect at  Sirius  making  the  so-called  "Egyptian  X." 

29.  Lynx  (Map  I.,  II.,  and  III.).  —  Returning  now  to  the  north- 
ern limit  of  the  map,  we  find  the  modern  constellation  of  the  Lynx 
lying  just  east  of  Auriga  and  enveloping  it  on  the  north  and  in  the 
circmnpolar  region.     It  contains  no  stars  above  the  fourth  magnitude, 
and  is  of  no  importance  except  as  occupying  an  otherwise  vacant 


Double  Stars.  (1)  38,  or  p  Lyncis,  A.R.  9h  llm;  Dec.  37°  21';  Mags. 
4,  7.5;  Pos.  240°;  Dist.  2".9;  white  and  lilac.  (This  is  the  northern 
one  of  a  pair  of  stars  which  closely  resembles  the  three  pairs  that 
mark  the  paws  of  Ursa  Major.  This  pair  makes  nearly  an  isosceles 
triangle  with  the  two  pairs  X  p.  and  i  K,  Ursse  Majoris  —  see  map.) 

30.  Gemini  (Map  II.).  —  This  is  the  fourth  of  the  zodiacal 
constellations  (mostly  in  the  sign  of  Cancer),  containing  the 
summer  solstitial  point  about  2°  west  and  a  little  north  of  the 
star  rj.  It  lies  northeast  of  Orion  and  southeast  of  Auriga, 
and  is  sufficiently  characterized  by  the  two  stars  a  and  /3  (about 
4£°  apart),  which  mark  the  heads  of  the  twins.  The  southern 

488 


§  30]  CANIS   MINOR.  23 

one,  fi,  or  POLLUX,  is  the  brighter,  but  a  (CASTOR)  is  much  the 
more  interesting,  as  being  double.  The  feet  are  marked  by 
the  third-magnitude  stars  y  and  /A,  some  10°  east  of  £  Tauri, 
and  the  map  shows  how  the  lines  that  join  these  to  ft  and  a 
respectively  mark  the  places  of  8  and  e.  77,  2°  west  of  /*,  is  a 
variable,  and  is  also  double,  though  as  such  it  is  beyond  the 
power  of  ordinary  telescopes. 

Names,  a,  CASTOR;  /?,  POLLUX;  y,  Alhena ,  /A,  Tejat  (Post)', 
rj,  Tejat  (Prior)  ;  8,  Wasat ;  e,  Meboula. 

Double  Stars.  (1)  a,  Mags.  2.5,  3  ;  Pos.  225°;  Dist.  5". 5.  Binary; 
period  undetermined,  but  certainly  over  200  years.  The  larger  of 
the  close  pair  is  also  a  spectroscopic  binary,  with  period  of  about  3 
days  (see  Art.  465*).  There  is  also  a  companion  of  ninth  mag.,  dis- 
tant about  74";  Pos.  164°.  (2)  8,  Mags.  3,  8  ;  Pos.  203°;  Dist  V'. 
(3)  ft,  Mags.  3,  11 ;  Pos.  79°;  Dist.  80". 

Nebula  and  Clusters.  (1)  M.  35;  A.R.  6h  Oln';  Dec.  24°  21';  N.W. 
of  r)  at  the  same  distance  as  that  from  /A  to  77,  and  on  the  line  from  y 
through  rj  produced.  The  map  is  not  quite  right  in  this  respect. 
(2)  $  IV.  45;  A.R.  7h  22m;  N.  21°  10'.  A  nebulous  star  in  a  small 
telescope  ;  in  a  large  telescope,  very  peculiar  —  2°  southeast  of  8. 

31.  Canis  Minor  (Map  II.).  — This  constellation,  just  south 
of  Gemini,  is  sufficiently  characterized  by  the  bright  star 
PROCYON,  which  is  25°  due  south  of  the  mid-point  between 
Castor  and  Pollux,  a,  ft,  and  y  together  form  a  configuration 
closely  resembling  that  formed  by  a,  ft,  and  y  Arietis.  Pro- 
cyon,  a  Orionis,  and  Sirius  form  nearly  an  equilateral  triangle 
with  sides  of  about  25°. 

Names,    a,  PROCYON  ;  {3,  Gomelza. 

Double  Stars.  (1)  Procyon  has  a  small  companion,  Dist.  40",  Pos. 
312°,  —  too  small,  however,  for  anything  less  than  an  8-inch  telescope. 
In  1896  a  still  smaller  companion,  like  that  of  Sirius,  was  found 
much  nearer  the  large  star.  (See  Art.  464.)  (2)  (2  1126)  (following 
Procyon  438,  and  2'  south,  —  the  brightest  of  the  stars  in  that  field), 
Mags.  7,  7.5  ;  Pos.  145°;  Dist.  1".5  ;  a  good  test  for  a  4-inch  glass. 

489 


24  URANOGRAPHY.  [§  32 

32.  Monoceros  (The  Unicorn)  (Map  II.).  — This  is  one  of  the 

new  constellations  organized  by  Hevelius  to  fill  the  gap  between  Gem- 
ini and  Canis  Minor  on  the  north,  and  Argo  Navis  and  Canis  Major 
on  the  south.  It  lies  just  east  of  Orion.  It  has  no  conspicuous  stars, 
but  is  traversed  by  a  brilliant  portion  of  the  Milky  Way.  The  a 
(fourth  mag.)  of  the  constellation  lies  about  half-way  between  a 
Orionis  and  Sirius,  a  little  west  of  the  line  joining  them. 

Double  Stars.  (1)  8,  or  6  (7£°  east  and  3°  south  of  a  Orionis), 
Mags.  5,  8 ;  Pos.  24° ;  Dist.  12".9  ;  colors,  orange  and  lilac.  A  fine 
low-power  field.  (2)  11  Monocerotis,  a  fine  triple  (see  Fig.  113  of 
Astr.),  A.R.  6h  24m ;  Dec.  south  6°  57';  A  to  B-C,  Pos.  130°,  Dist.  8"; 
B-C,  Pos.  120°,  Dist.  2".5.  The  star  is  very  nearly  pointed  at  by  a 
line  drawn  from  £  Canis  Majoris,  north  through  ft,  and  continued  as 
far  again. 

Clusters.  (1)  #  VII.  2 ;  A.R.  6h  24m ;  Dec.  N.  5°  2'  (visible  to  the 
naked  eye  about  1.]°  N.E.  of  8  Monocerotis  described  above).  A  fine 
cluster  for  a  low  power.  (2)  M.  50 ;  A.R.  6h  57m ;  Dec.  S.  8°  9'. 
In  the  Milky  Way,  on  the  line  from  Sirius  to  Procyon,  two-fifths  of 
the  distance. 

33.  Canis  Major  (Map  II.).  —  This  glorious  constellation 
needs  no  description.     Its  a  is  the  Dog  Star,  SIRIUS,  beyond 
all  comparison  the  brightest  in  the  heavens,  and  probably  one 
of  our  nearer  neighbors.     It  is  nearly  pointed  at  by  the  line 
drawn  through  the  three  stars  of  Orion's  belt.     /?,  at  the  ex- 
tremity of  the  uplifted  paw,  is  of  the  second  magnitude,  and 
so  are  several  of  those  farther  south  in  the  rump  and  tail  of 
the  animal,  who  sits  up  watching  his  master  Orion,  but  with 
an  eye  out  for  Lepus. 

Names,  a,  SIRIUS;  ft,  Mirzam;  y,  Muliphen ;  8,  Wesen;  c,  Adara. 
y  is  said  to  have  disappeared  from  1670  to  1690,  but  at  present  is  not 
recognized  as  variable,  though  much  fainter  than  would  be  expected 
from  its  being  lettered  as  y. 

Double  Stars.  (1)  Sirius  itself  has  a  small  companion  (see  Art. 
463).  (2)  fji  (4°  N.E.  of  Sirius),  Mags.  5,  9.5  ;  Pos.  335°;  Dist.  3".5. 

Clusters.  (1)  M.  41  (4°  south  of  Sirius)  ;  a  fine  group  with  a  red 
star  near  centre. 

490 


§  34]  ARGO  NAVIS.  25 

34.  Argo  Navis  (The  Ship)  (Maps  II.  and  in.).  —  This  is  one 
of  the  largest,  most  important,  and  oldest  of  the  constellations,  lying 
south  and  east  of  Canis  Major.     Many  Uranographers  now  divide  it 
into  three,  Puppis,  Vela,  and  Carina.     Its  brightest  star,  a  Argus, 
CANOPUS,  ranks  next  to  Sirius,  but  is  not  visible  anywhere  north  of 
the  parallel  of  38°.     The  constellation,  huge  as  it  is,  is  only  a  half 
one,  like  Pegasus  and  Taurus,  —  only  the  stern  of  a  vessel,  with 
mast,  sail,  and  oars  ;  the  stern  being  wanting.     In  the  part  of  the 
constellation  covered  by  our  maps  the  most  conspicuous  stars  lie  east 
and  southeast  of  Canis  Major.    We  have  already  mentioned  £,  or  Naos 
(Art.  28),  at  the  southeast  extremity  of  the  "Egyptian  X";  and  about 
8°  south  and  a  little  east  of  it  is  y,  nearly  of  the  second  magnitude. 

Clusters.  One  or  two  clusters  are  accessible  in  our  latitudes. 
(1)  (#  VIII.  38),  A.R.  7h  31in;  Dec.  S.  14°  12'.  Pointed  at  by  the  line 
from  ft  Can.  Maj.  through  Sirius,  continued  2J  times  as  far.  Visible 
to  naked  eye;  rather  coarse.  (2)  M.  46;  a  little  more  than  1°  east 
and  south  of  the  preceding.  (3)  M.  93,  A.R.  7h  391" ;  Dec.  S.  23°  34'; 
about  2°  N.W.  of  £  Argus. 

35.  Cancer  (Maps  II.  and  III.).  — This  is  the  fifth  of  the 
zodiacal  constellations,  bounded  north  by  Lynx  and  Leo  Minor, 
south  by  the  head  of  Hydra,  west  by  Gemini  and  Canis  Minor, 
and  east  by  Leo.     It  does  not  contain  a  single  conspicuous 
star,  but  is  easily  recognizable  from  its  position,  and  in  a  dark 
night   by  the   nebulous   cloud   known   as  "Praesepe,"  or  the 
"Manger,"  with  the  two  stars  y  and  8  near  it,  —  the  so-called 
"  Aselli,"  or  "  Donkeys."    Praesepe  (sometimes  also  called  the 
"Beehive")  is  really  a  coarse  cluster  of  seventh -and  eighth 
magnitude  stars,  resolvable  by  an  opera-glass.     The  line  from 
Castor  through  Pollux,  produced  about  12°,  passes  near  enough 
to  it  to  serve  as  a  pointer,     a,  of  the  fourth  magnitude,  is  on 
the  line  drawn  from  Praesepe  through  8  (the  southern  Asellus), 
produced  about  7°;  ft  may  be  recognized  by  drawing  a  line 
from  y  (the  northern  .Asellus)  through  Prsesepe,  and  continu- 
ing it  about  12°. 

Double  Stars.  (1)  t,  Mags.  4,  6.5 ;  Pos.  308°;  Dist.  30  ';  orange  and 
blue ;  nearly  due  north  of  y,  distance  twice  that  between  the  Aselli. 

491 


26  URANOGRAPHY.  [§  35 

(2)  £  Triple  (see  Astr.  Fig.  113);  A-B,  Mags.  6  and  7,  Pos.(1905) 
346°,  Dist.  1";  in  rapid  motion;  period  about  60  years.  A-C,  Pos. 
(1905)  110°,  Dist.  5";  also  in  motion,  but  period  unknown  and  much 
longer.  Easily  found  by  a  line  from  a  Gem.  through  ft,  produced  two 
and  a  half  times  as  far. 

36.  Leo  (Map  III.). — East  of   Cancer  lies  the  noble  con- 
stellation of  Leo,  which  adorns  the  evening  sky  in  March  and 
April ;  it  is  the  sixth  of  the  zodiacal  constellations,  now  occu- 
pying the  sign  of  Virgo.     Its  leading  star  REGULUS,  or  "  Cor 
Leonis"  is  of  the  first  magnitude,  and  two  others,  ft  and  y,  are 
of  the   second,     a,  y,  8,  and  ft  form  a  conspicuous  irregular 
quadrilateral  (see  map),  the  line  from  Regulus  to  Denebola 
being  26°  long.     Another  characteristic  configuration  is  "The 
Sickle,"  of  which  a,  t]  is  the  handle,  and  the  curved  line  rj,  y,  £, 
/*,  and  e  is  the  blade,  the  cutting  edge  being  turned  towards 
Cancer.     The  "  radiant "  of  the  November  meteors  lies  between 
£  and  e. 

Names,    a,  REGULUS;  ft,  DENEBOLA;  y,  Algeiba;  8,  Zosma. 

Double  Stars.  (1)  y,  Mags.  2,  3.5;  Pos.  116°;  Dist.  3".4;  binary; 
period  about  400  years.  (2)  i,  Mags.  4  and  7;  Pos.  65°;  Dist.  2".5; 
yellow  and  bluish  ;  easily  recognized  by  aid  of  the  map.  (3)  54, 
Mags.  4.5,  7;  Pos.  103°;  Dist.  6".2.  Found  by  producing  the  line 
from  ft  through  8  half  its  length. 

37.  Leo  Minor  and  Sextans  (Map  III.).  —  Leo  Minor  is  an 
insignificant  modern  constellation  composed  of  a  few  small  stars  north 
of  Leo,  between  it  and  the  hind  feet  of  Ursa  Major.      It  contains 
nothing  deserving  special  notice.     A  similar  remark  holds  as  to  Sex- 
tans even  more  emphatically. 

38.  Hydra  (Map  III.). — This  constellation,  with  its  riders 
Crater  and  Corvus,  is  a  large  and  important  one,  though  not 
very  brilliant.     The  head  is  marked  by  a  group  of  five  or  six 
fourth  and  fifth  magnitude  stars  just  15°  south  of  Prsesepe. 
A  curving  line  of  small  stars  leads  down  southeast  to  a,  "  Cor 
Hydrce"  a  small  second  or  bright  third  magnitude  star  stand- 

492 


§  38]  VIRGO.  27 

ing  very  much,  alone.  From  there,  as  the  map  shows,  an 
irregular  line  of  fourth-magnitude  stars  running  far  south  and 
then  east,  almost  to  the  boundary  of  Scorpio,  marks  the  crea- 
ture's body  and  tail,  the  whole  covering  almost  six  hours  of 
right  ascension,  and  very  nearly  90°  of  the  sky.  About  the 
middle  of  his  length,  and  just  below  the  hind  feet  of  Leo  (30° 
due  south  from  Denebola),  we  find  the  little  constellation  of 
Crater;  and  just  east  of  it  the  still  smaller  but  much  more 
conspicuous  one  of  Corvus,  with  two  second-magnitude  stars 
•in  it,  and  four  of  the  third  and  fourth  magnitudes.  It  is  well 
marked  by  a  characteristic  quadrilateral  (see  map);  with  8  and 
rj  together  at  its  northeast  corner.  The  order  of  the  letters 
differs  widely  from  that  of  brightness  in  this  constellation, 
suggesting  that  changes  may  have  occurred. 

Names,  a  Hydrre,  ALPHARD  or  Cor  Hydrce;  a  Crateris,  Alkes; 
a  Corvi,  Alchiba  ;  8  Corvi,  Algores.  / 

Double  Stars.  (1)  e  Hydras  (the  northernmost  one  of  the  group 
that  marks  the  head),  Mags.  4,  8;  Pos.  220°;  Dist.  3".5 ;  yellow  and 
purple.  (2)  8  Corvi,  Mags.  3,  8;  Pos.  210°;  Dist.  24";  yellow 
and  purple.  (3)  Nebula,  T§.  IV.  27,  A.R.  10"  19'";  Dec.  S.  18°  2'  (3° 
S.  and  £°  W.  of  /x  —  see  map).  Bright  planetary  nebula,  about  as 
large  as  Jupiter. 

39.  Virgo  (Map  III.).— East  and  south  of  Leo  lies  Virgo, 
the  seventh  zodiacal  constellation,  bounded  on  the  north  by 
Bootes  and  Coma  Berenicis,  on  the  east  by  Bootes  and  Libra, 
and  on  the  south  by  Gorvus  and  Hydra.  Its  a,  SPICA  Vir- 
ginis,  is  of  the  1|-  magnitude  and,  standing  rather  alone  10° 
south  of  the  celestial  equator,  is  easily  recognized  as  the 
southern  apex  of  a  nearly  equilateral  triangle  which  it  forms 
with  Denebola  (ft  Leonis)  to  the  northwest,  and  Arcturus 
northeast  of  it.  (3  Virgiriis  of  the  third  magnitude  is  14°  due 
south  of  Denebola.  A  line  drawn  eastward  and  a  little  south 
from  ft  (third  magnitude)  and  then  carried  on,  curving  north- 
ward, passes  successively  (see  map)  through  77,  y,  S,  and  c, 

493 


28  UBAKOGRAPHY.  [§  39 

of  the  third  magnitude  (notice  the  word  formed  by  the  letters 
Begde,  like  Bagdei  in  Cassiopeia,  Art.  9).  0  lies  nearly  mid- 
way between  a  and  8.  There  are  also  a  number  of  other  fourth- 
magnitude  stars. 

Names,     a,  SPICA  and  Azimech;  /3,  Zavijava;  e,  Vindemiatrix. 

Double  Stars.  (1)  y,  (Binary;  period  185  years;  not  quite  half-way 
from  Spica  to  Denebola,  and  a  little  west  of  the  line),  Mags.  3,  3;  Pos. 
(1905)  328°;  Dist.  G".2;  very  easy  and  fine  (Astr.  Fig.  113).  (2)  0 
(two-fifths  of  the  way  from  Spica  towards  8),  Triple;  Mags.  A  4.5, 
B  9,  C  10;  Pos.  A-B,  345°,  Dist.  7";  A-C,  Pos.  295°,  Dist.  65". 
(3)  o  (one-third  of  the  way  from  Denebola  towards  y  Virginis), 
Mags.  6  and  8 ;  Pos.  228° ;  Dist.  3".5.  Spica  is  a  spectroscopic 
binary  (Art.  465*). 

Nebulce.  (1)  M.  49  ;  A.R.  12'1  24'"  ;  Dec.  +  8°  40'.  Forms  an  equi- 
lateral triangle  with  B  and  e.  It  lies  in  the  remarkable  "  nebulous  " 
region  of  Virgo.  But  most  of  the  nebulae  are  faint,  and  observable 
only  with  large  telescopes.  (2)  $  IT.  74  and  75;  A.R.  12"  47m  ;  Dec. 
+  11°  53' ;  two  in  one  field,  2°  west  and  a  little  north  of  e.  (3)  M.  86 
(midway  between  Denebola  and  e)  ;  A.R.  12h  20m  ;  Dec.  +  13°  30  .  A 
large  telescope  shows  nearly  a  dozen  nebulae  within  2°  of  this  place. 

40.  Coma  Berenicis  (Map  III.).  — This  little  constellation,  com- 
posed of  a  great  number  of  fifth  and  sixth  magnitude  stars,  lies  30° 
north  of  y  and  rj  Virginis,  and  about  15°  northeast  of  Denebola.     It 
contains  a  number  of  interesting  double  stars,  but  they  are  not  easily 
found  without  the  help  of   an  equatorial  mounting  and  graduated 
circles. 

41.  Canes  Venatici  (The  Hunting  Dogs).  —  These  are  the 
dogs  with  which  Bootes  is  pursuing  the  Great  Bear  around  the 
pole :  the  northern  of  the  two  is  Asterion,  the  southern  CJiara. 
Most  of  the  stars  are  small,  but  a  is  of  the  2J-  magnitude,  and 
is  easily  found  by  drawing  from  rj  Ursae  Majoris  (the  star  in 
the  end  of  the  Dipper-handle)  a  line  to  the  southwest,  perpen- 
dicular to  the  line  from  77  to  £  (Mizar)  and  about  15°  long :  it 
is  about  one-third  of  the  way  from  rj  Ursse  Majoris  to  8  Leonis. 
With  Arcturus  and  Denebola  it  forms  a  triangle  much  like 
that  which  they  form  with  Spica. 

494 


§  41]  BOOTES.  29 

Names,     a  is  known  as  Cor  Carol!  (Charles  II.  of  England). 

Double  Stars.  (1)  a,  or  12  Canum,  Mags.  3  and  5 ;  Pos.  227°;  Dist. 
20".  (2)  2  Canum  (one-third  of  the  way  from  a  towards  8  Leonis), 
Mags.  6  and  8 ;  Pos.  260° ;  Dist.  41".3 ;  orange,  smalt  blue. 

Nebulae.  (1)  M.  51 ;  A.R.  13h  25ra ;  Dec.  47°  49'  (3°  west  and  some, 
what  south  of  Benetnasch).  A  faint  double  nebula  in  small  tele- 
scopes; in  great  ones,  the  wonderful  "Whirlpool  Nebula,"  of  Lord 
Rosse.  (2)  M.  3 ;  bright  cluster  (half  a  degree  north  of  the  line  from 
a  Canum  to  Arcturus,  and  a  little  nearer  the  latter).  It  is  one  of 
the  variable-star  dusters  discovered  in  1895  (see  Art.  455*). 

42.  Bootes  (Maps  III.  and  I.).  —  This  fine  constellation  is 
bounded  on  the  west  by  Ursa  Major,  Canes  Venatici,  Coma, 
Berenicis,  and  Virgo,  and  on  the  south  by  Virgo.  It  extends 
more  than  60°  in  declination,  from  near  the  equator  quite  to 
Draco,  where  the  uplifted  hand  overlaps  the  tail  of  the  Bear. 
Its  principal  star,  ARCTURUS,  is  of  a  ruddy  hue,  and  in  bright- 
ness is  excelled  only  by  Sirius  among  the  stars  visible  in  our 
latitudes.  Canopus  and  a  Centauri  are  reckoned  brighter,  but 
they  are  southern  circumpolars.  Arcturus  is  at  once  recog- 
nized by  its  forming  with  Spica  and  Denebola  the  great  tri- 
angle already  mentioned  (Art.  39).  Six  degrees  west  and  a 
little  south  of  it  is  ^  of  the  third  magnitude,  which  forms 
with  it,  in  connection  with  v,  a  configuration  like  that  in  the 
head  of  Aries,  c  is  about  10°  northeast  of  Arcturus,  and  in 
the  same  direction  about  10°  farther  lies  8.  A  pentagon  is 
formed  by  these  two  stars  along  with  /?,  y,  and  p.  "  Bootes  " 
means  "the  shouter"  (or,  according  to  others,  "the  herds- 
man"). 

Names,  a,  ARCTURUS;  y8,  Nekkar;  c,  Izar;  rj,  Muphrid;  y, 
Seginus. 

Double  Stars.  (1)  e,  Mags.  3,  6;  Pos.  325°;  Dist.  3".l ;  orange  and 
greenish  blue ;  very  fine.  (2)  £  (about  9°  southeast  from  Arcturus, 
at  right  angles  to  the  line  ae),  Mags.  3.5,  4;  Pos.  295°;  Dist.  0".8: 
a  good  test  for  a  4-inch  glass.  (3)  TT  (2^°  north  of  £),  Mags.  4.9,  6 ; 
Pos.  101°;  Dist.  5".3.  (4)  £  (10°  due  east  from  Arcturus,  3°  N.E. 
from  TT),  Mags.  4.7,  G.6;  Pos.  (1905)176°;  Dist.  2".5;  yellow  and  purple. 
Binary ;  period  127  years. 

495 


80  URANOGRAPHY.  [§  43 

43.  Corona  Borealis  (Map  III.).  — This  beautiful  little  con- 
stellation lies  20°  northeast  of  Arcturus,  and  is  at  once  rec- 
ognizable as  an  almost  perfect  semicircle  composed  of  half  a 
dozen  stars,  among  which  the  brightest,  a,  is  of  the  second 
magnitude.     The  extreme  northern  one  is  0;  next  comes  J3, 
and  the  rest  follow  in  the  ft  a  y  8  e  t   (Bagdei)  order,  just  as 
in  Cassiopeia. 

Names,     a,  Gemma,  or  Alphacca. 

Double  Stars.  (1)  £  (nearly  pointed  at  by  €-8  Bobtis  ;  7°  from  c), 
Mags.  5,  6;  Pos.  301°;  Dist.  G";  white  and  greenish.  (2)  rj,  rapid 
binary,  at  certain  times  can  be  split  by  a  4-inch  glass.  Mags.  G,  G.5; 
pointed  at  by  the  line  from  a  through  ft,  2°  beyond  ft.  The  tempo- 
rary star  of  1866  (Astr.  450)  lies  1J°  S.E.  of  c  Coronse. 

44.  Libra  (Map  III.).  —  This  is  the  eighth  of  the  zodiacal 
constellations,  and  lies  east  of  Virgo,  bounded  on  the  south  by 
Centaurus  and  Lupus,  on  the  east  by  the  upstretched  claw  of 
Scorpio,  and  on  the  north  by  Serpens  and  Virgo.     It  is  incon- 
spicuous, the  most  characteristic  figure   being  the   trapezoid 
formed  by  the  lines  joining  the  four  stars  a,  i,  y,  ft.     (3,  which 
is  the  northernmost  of  the  four,  is  the  brightest  (2|  magni- 
tude), and  is  about  30°  nearly  due  east  from  Spica,  while  a  is 
about  10°  southwest  of  ft.     The  remarkable  variable  8  Librae 
is  4°  west  and  a  little  north  from  ft.     Most  of  the  time  it  is 
of  the  41  or  fifth  magnitude,  but  runs  down  nearly  two  magni- 
tudes at  the  minimum. 

Names,     a,  Zuben  el  Genubi;  ft,  Zuben  el  Cliamali. 

Cluster.  M.  5;  A.R.  15"  12"';  Dec.  N.  2°  32'.  This  is  within  the 
boundaries  of  Serpens,  and  just  a  little  north  and  west  of  the  fifth- 
magnitude  star  5  Serpentis.  It  is  a  variable-star  cluster  (Art.  455*). 

45.  Antlia,  Centaurus,  and  Lupus  (Map  III.).  — These  constel- 
lations lie  south  of  Hydra  and  Libra.    Antlla  Pneumatica  (the  "  Air- 
Pump")  is  a  modern  constellation  of  no  importance  and  hardly  recog- 
nizable by  the  eye,  having  only  a  single  star  as  bright  as  the  4}  mag- 

496 


§  45]  SCORPIO.  31 

nitude.  Centaurus,  on  the  other  hand,  is  an  ancient  and  extensive 
asterism,  containing  in  its  (south)  circumpolar  portion  two  stars  of 
the  first  magnitude  :  a  Centauri  stands  next  after  Sirius  and  Canopus 
in  brightness,  and,  as  far  as  present  knowledge  indicates,  is  our  nearest- 
neighbor  among  the  stars.  The  part  of  the  constellation  which  be- 
comes visible  in  our  latitudes  is  not  specially  brilliant,  though  it  con- 
tains several  stars  of  the  2£  and  third  magnitude  in  the  region  that 
lies  south  of  Corviis  and  Spica  Virginis.  A  line  from  €  Virginis 
through  Spica,  produced  a  little  more  than  its  own  length,  will  strike 
very  near  0,  a  solitary  star  of  the  2]  magnitude  in  the  Centaur's 
left  shoulder,  i  (third  mag.)  lies  11°  west  of  0,  and  rj  (third  mag.) 
9°  southeast;  while  5°  or  6U  south  of  the  line  from  0  to  i  lies  a  tangle 
of  third-magnitude  stars,  which,  if  they  were  at  a  higher  elevation, 
would  be  conspicuous.  Centaurus  is  best  seen  in  May  or  early  in 
June. 

Lupus,  also  one  of  Ptolemy's  constellations,  lies  due  east  of  Cen- 
taurus and  just  south  of  Libra.  It  contains  a  considerable  number  of 
third  and  fourth  magnitude  stars  ;  but  is  too  low  for  any  satisfactory 
study  in  our  own  latitudes.  It  is  best  seen  late  in  June.  These 
constellations  contain  numerous  objects  interesting  for  a  southern 
observer,  but  nothing  available  for  our  purpose. 

46.  Scorpio  (or  Scorpius)  (Map  III.). — This,  the  ninth  of 
the  zodiacal  constellations,  and  the  most  brilliant  of  them, 
lies  southeast  of  Libra,  which  in  ancient  times  used  to  form 
its  claws  (Chelce).  It  is  bounded  north  by  Ophiuchus,  south 
by  Lupus,  Norma,  and  Ara,  and  east  by  Sagittarius.  It  is 
recognizable  at  once  on  a  summer  evening  by  the  peculiar  con- 
figuration, like  a  boy's  kite,  with  a  long  streaming  tail  reach- 
ing far  down  to  the  southern  horizon.  Its  principal  star, 
ANTARES,  is  .of  the  first  magnitude  and  fiery  red,  like  the 
planet  Mars.  From  this  it  gets  its  name,  which  means  "the 
rival  of  Ares  "  (Mars) .  (3  (second  magnitude)  is  in  the  arch 
of  the  kite  bow,  about  8°  or  9°  northwest  of  Antares,  while 
the  star  which  Bayer  lettered  as  y  Scorpii  is  well  within  Libra, 
20°  west  of  Antares.  (There  is  no  little  discordance  and  con- 
fusion among  Uranographers  as  to  the  boundary  between  the 

497 


32  TJRANOGRAPHY.  [§  46 

two  constellations.)  The  other  principal  stars  of  the  constel- 
lation are  easily  found  on  the  map ;  8  is  3°  southwest  of  /?, 
while  e,  £,  rj,  0,  i,  K,  and  A.  follow  along  in  order  in  the  tail  of 
the  creature,  except  that  between  e  and  £  is  interposed  the 
double  p.  £,  0,  and  A  are  all  of  the  second  magnitude,  and  the 
others  of  the  third. 

47.  Names,    a,  ANTARES  ;  /?,  Akrdb. 

Double  Stars.  (1)  a,  Mags.  1  and  7 ;  Pos.  270° ;  Dist.  3.  "5 ;  fiery  red 
and  vivid  green.  A  beautiful  object  when  the  state  of  the  air  allows 
it  to  be  well  seen.  (2)  (3,  Triple ;  Mags.  A  2,  B  4,  C  10 ;  A-B,  Pos. 
25°,  Dist.  13";  A-C,  Pos.  89°,  Dist.  0".9.  (3)  v  (2°  due  east  of  /3), 
Quadruple ;  Mags.  A  4,  B  5,  C  7,  D  8 ;  A-B,  Pos.  7°,  Dist.  0".S ; 
A-C,  Pos.  337°,  Dist.  41";  C-D,  Pos.  47°,  Dist.  2".4.  A  beautiful 
object.  (4)  i  Scorpii  (81°  due  north  from  £),  Triple;  Mags.  A  5, 
B  5.2,  C  7.5  ;  A-B,  (Binary)  Pos.  200°,  Dist.  1".4  ;  £(A  +  B)  to  C,- 
Pos.  65°,  Dist.  7".3.  /a1  is  a  spectroscopic  binary  (Art.  465*). 

Clusters.  (1)  M.  80,  A.R.  16h  10ra:  Dec.  S.  22°  42';  half-way 
between  a  and  /?;  one  of  the  finest  clusters  known.  (2)  M.  4,  A.R. 
16h  16m;  Dec.  S.  26°  14';  U°  west  of  a;  not  so  fine  as  the  preceding. 

Norma  lies  west  of  Scorpio,  between  it  and  Lupus,  while  Ara  lies 
due  south  of  17  and  0.  Both  are  small  and  of  little  importance,  at 
least  to  observers  in  our  latitudes. 

48.  Ophmchus  (or  Serpentarius)  and  Serpens  (Map  III.).  — 
Ophiuchus  means  the  "serpent-holder."     The  giant  is  repre- 
sented as  standing  with  his  feet  on  Scorpio,  and  grasping  the 
"  serpent,"  the  head  of  which  is  just  south  of  Corona  Borealis, 
while  the  tail  extends  nearly  to  Aquila.     The  two  constella- 
tions therefore  are  best  treated  together.     The  head  of  Serpens 
is  marked  by  a  group  of  small  stars  20°  due  east  of  Arcturus, 
and  10°  south  of  Corona.     (3  and  y  are  the  two  brightest  stars 
in  the  group,  their  magnitudes  three  and  a  half  and  four. 
8  lies  6°  southwest  of  /?,  and  there  the  serpent's  body  bends 
southeast  through  a  and  c  Serpentis  (see  map)  to  8  and  e  Ophi- 
uchi  in  the  giant's  hand.     The  line  of  these  five  stars  carried 
upwards    passes    nearly   through   e    Bootis,    and    downwards 

498 


§  48]  OPHIUCHTTS.  33 

through  £  Ophiuchi.  A  line  crossing  this  at  right  angles, 
nearly  midway  between  e  Serpentis  and  8  Ophiuchi,  passes 
through  //,  Serpentis  on  the  southwest,  and  X  Ophiuchi  to  the 
northeast.  The  lozenge-shaped  figure  formed  by  the  lines 
drawn  from  a  Serpentis  and  £  Ophiuchi  to  the  two  stars  last 
mentioned  forms  one  of  the  most  characteristic  configurations 
of  the  summer  sky. 

a  Ophiuchi  (2^-  magnitude)  is  easily  recognized  in  connection 
with  a,  Herculis,  since  they '  stand  rather  isolated,  about  6° 
apart,  on  the  line  drawn  from  Arcturus  through  the  head  of 
Serpens,  and  produced  as  far  again,  a  Ophiuchi  is  the  eastern 
and  the  brighter  of  the  two.  It  forms  with  Vega  and  Altair  a 
nearly  equilateral  triangle,  ft  Ophiuchi  lies  about  9°  southeast 
of  a  j  and  5°  east  and  a  little  south  of  /?  are  five  small  stars 
in  the  Milky  Way,  forming  a  V  with  the  point  to  the  south, 
much  like  the  Hyades  of  Taurus.  They  form  the  head  of  the 
now  discredited  constellation  " Poniatowski's  Bull"  (Taurus 
Poniatovii) ,  proposed  in  1777. 

49.  Names,  a.  Ophiuchi,  Ras  AlagJme  ;  /3,  Cebalrai ;  8,  Yed ;  X, 
Marjic:  a.  Serpentis,  Unukalhai ;  0,  Alya. 

Double  Stars.  (1)  X  Ophiuchi,  Binary ;  period,  234  years ;  Mags.  4, 
6  ;  Pos.  (1905)  60°  ;  Dist.  1".2.  (2)  70  Ophiuchi  (the  middle  star  in 
the  eastern  leg  of  the  V  of  Poniatowski's  Bull),  Binary;  period,  93 
years ;  Mags.  4.5,  7;  Pos.  (1905)  180°  ;  Dist.  2".  The  position  angle 
changes  very  rapidly  just  now,  and  the  star  is  too  close  to  be  resolved 
by  a  small  instrument.  (°>)  8  Serpentis,  Mags.  4,  5 ;  Pos.  185° ;  Dist. 
3  ".6 ;  very  pretty.  (4)  0  Serpentis,  Mags.  4,  4.5;  Pos.  104°;  Dist.  21". 
(5)  v  Serpentis  (4°  N.E.  of  rj  Ophiuchi),  Mags.  4.5,  9 ;  Pos.  31°;  Dist. 
51"  ;  sea-green  and  lilac. 

Clusters.  (1)  M.  23,  A.R.  17h  50ra ;  Dec.  S.  19°  0'.  Fine  low- 
power  field.  (2)  M.  12,  A.R.  16h  41m ;  Dec.  S.  1°  45'.  On  the  line 
between  {3  and  €  Ophiuchi,  one-third  of  the  way  from  e.  (3)  M.  10, 
A.R.  16"  51m  ;  Dec.  S.  3°  56'.  On  the  line  between  @  and  £  Ophiuchi, 
two-fifths  of  the  way  from  £.  (4)  %  VIII.  72,  A.R.  18h  22m ;  Dec.  N. 
6°  29'.  Pointed  at  by  the  eastern  leg  of  the  Poniatowsld  V.  8°  from 
70  Ophiuchi. 

499 


84  URANOGRAPHY.  [  §  50 

50.  Hercules  (Maps  I.  and  III.).  —  This  noble  constellation 
lies  next  north  of  Ophiuchus,  and  is  bounded  on  the  west  by 
Serpens,  Corona,  and  Bootes,  while  to  the  east  lie  Aquila,  Lyra, 
and  Cygnus.     On  the  north  is  Draco.     The  hero  is  represented 
as  resting  on  one  knee,  with  his  foot  on  the  head  of  Draco, 
while  his  head  is  close  to  that  of  Ophiuehus.     The  constella- 
tion contains  no  stars  of  the  first  or  even  of  the  second  mag- 
nitude, but  a  number  of  the  third.     The  most  characteristic 
figure  is  the  keystone-shaped  quadrilateral  formed  by  the  stars 
€,  £,.  rj,  with  TT  and  p  together  at  the  northeast  corner.     It  lies 
about  midway  on  the  line  from  Vega  to  Corona.     The  line  TTC, 
carried  on  11°,  brings  us  to  (3,  the  brightest  star  of  the  aster- 
ism  ;  and  y  and  K  lie  a  few  degrees  farther  along  on  the  same 
line  continued  toward  y  Serpentis.     The  angle  e/3a  is  a  right 
angle  opening  towards  Lyra,     a  is  irregularly  variable,  besides 
being  double. 

51.  Names,    a,  Ras  AlgetJii ;  /?,  Korneforos. 

Double  Stars.  (1)  a,  Mags.  3,  6 ;  Pos.  119°;  Dist.  4  ".5 ;  orange  and 
blue.  A  very  beautiful  object  for  a  4-inch  glass  (Astr.  Fig.  113).  (2)  £ 
(the  S.W.  corner  of  the  "Keystone"),  Binary  ;  period,  3-4  y.  (Astr.  Fig. 
113);  Mags.  3,6.5  ;  Pos.  (1905)  190°;  Dist.  1".5.  Rather  difficult  for  a 
small  instrument.  (3)  p  (2.}°  east  of  TT  at  the  N".W.  corner  of  the 
"  Keystone  "),  Mags.  4,  5  ;  Pos.  312°  ;  Dist.  4"  ;  white,  emerald  green. 
(4)  8  (on  the  line  from  rj  through  €  produced  nearly  its  own  length), 
Mags.  3,  8 ;  Pos.  184° ;  Dist.  18"  ;  white,  light  blue.  Apparently  an 
"  optical  pair  ";  the  relative  motion  being  rectilinear.  (5)  p  (nearly 
midway  between  Vega  and  a  Herculis  —  see  map),  Triple]  Mags.  A  4, 
B  9.5,  CIO;  A,  B+.C,  Pos.  246° ;  Dist.  31".  B-C,  too  faint  and  close 

for  separation  by  any  but  large  telescopes;  Dist.  about.  1";  position 
angle  rapidly  changing  —  about  20°  in  1890.  (G)  1)5  Herculis  (the 
N.W.  corner  of  a  little  quadrilateral  [sides  1°  to  2°]  of  fourth  and 
fifth  mag.  stars,  on  line  from  p  through  p.,  produced  two-thirds  its 
length),  Mags.  5.5  and  6;  Pos.  262°;  Dist.  6";  light  green,  cherry-red. 
Peculiar  in  showing  contrast  of  color  between  nearly  equal  components. 
Clusters.  (1)  M.  13,  A.R.  16h  37 m  ;  Dec.  36°  41'.  Exactly  on  the 
western  boundary  of  the  Keystone,  one-third  the  way  from  rj  towards 

600 


§  61]  LYRA.  35 

£.  On  the  whole,  the  finest  of  all  star  clusters.  (2)  M.  92,  A.R. 
17h  13'"  ;  Dec.  43°  16'  (0°  north  and  a  little  west  of  p).  Fine,  but  not 
equal  to  the  other. 

52.  Lyra  (Map  IV.).  —  The  great  white  or  blue  star  VEGA 
sufficiently  marks  this  constellation.     It  is  amended  on  the 
east  by  two  fourth-magnitude  stars,  e  and  £,  which  form  with 
it  a  little  equilateral  triangle  having  sides  al  out  2°  long,     ft 
and  y  of  the  third  magnitude   (ft  is  variable)  lie  about  8° 
southeast  from  Vega,  2£°  apart. 

Double  Stars.  (1)  Vega  itself  has  a  small  companion,  llth  mag. ; 
Pos.  V300;  Dist.  48".  Only  optically  connected ;  the  small  star  does 
not  share  the  proper  motion  of  the  larger  one,  and  has  been  used  as  a 
reference  point  in  measuring  Vega's  parallax.  (2)  ft,  multiple;  i.e., 
it  has  three  small  stars  near  it,  forming  a  very  pretty  object  with  a 
low  power.  (3)  e:  and  e2,  Quadruple  (the  northern  of  the  two  which 
form  the  little  triangle  with  a.)  A  sharp  eye  unaided  by  a  telescope 
splits  the  star,  and  a  small  telescope  divides  both  the  components 
(see  Astr.  468,  and  Fig.  113):  ex  (or  4  Lyrae),  Mags.  6,  7;  Pos.  12°; 
Dist.  3".2.  e,  (or  5  Lyrse),  Mags.  5.5,  6;  Pos.  132°;  Dist.  2".o.  €l  c2, 
Pos.  173°;  Dist.  207".  On  the  whole,  the  finest  object  of  the  kind. 
(4)  £,  Mags,  4,  6;  Pos.  150°;  Dist.  44".  (5)  rj  (10°  E.  of  Vega), 
Mags.  4.5,  8;  Pos.  85°;  Dist.  28";  yellow,  indigo.  (<>)  8;  fine  field 
for  low  powers. 

Nebula.  M.  57,  the  Annular  Nebula.  A.R.  18h  49m  ;  Dec.  32°  53'. 
Between  ft  and  y,  one-third  of  the  way  from  ft.  (Art.  470.) 

53.  Cygnus  (Maps  I.  and  IV.).  —  This  lies  due  east  from 
Lyra,  and  is  easily  recognized  by  the  cross  that  marks  it.   The 
bright  star  a  (1^  magnitude)  is  at  the  top,  r,nd  ft  (third  mag- 
nitude) at  the  bottom,  while  y  is  where  the  cross-7 >ar  from  d  to 
e  intersects  the  main  piece,  which  lies  along  th  3  Milky  Way 
from  the  northeast  to  the  southwest.     £  is  (nearly)  on  the  pro- 
longation of  the  line  from  y  through  e,  not  quite  so  far  from 
E  as  e  from  y. 

Names,  a,  Arided,  or  Deneb  Cygni  (there  are  other  Denebs ;  e.g., 
Deneb  Kaitos  in  Cetus)  ;  ft,  Albireo ;  y,  Sadr. 

501 


36  URANOGRAPHY.  [§  53 

Double  Stars.  (1)  ft,  Mags.  3.5,  7;  Pos.  56°;  Dist.  35";  orange, 
smalt  blue.  This  is  the  finest  of  the  colored  pairs  for  a  small  tele- 
scope. (2)  fji  (as  far  beyond  £  as  £  is  east  of  c,  at  the  tip  of  the  east- 
ern wing),  Mags.  5  and  6;  Pos.  118°;  Dist.  3".8.  (3)  %  (one-third  of 
the  way  from  ft  towards  y),  Mags.  5  and  9  ;  Pos.  73°;  Dist.  26";  yel- 
low and  blue.  (4)  61  Cygni  (easily  found  by  completing  the  parallel- 
ogram of  which  a,  y,  and  e  are  the  other  three  corners,  a-  and  r  form 
a  little  triangle  with  61,  which  is  the  faintest  of  the  three),  Mags. 
5.5,  6;  Pos.  (1905)  127°;  Dist.  22".  This  is  the  star  of  which  Bessel 
measured  the  parallax  in  1838  (Astr.  521),  —  apparently  our  second 
nearest  neighbor. 

8  is  also  a  fine  double,  but  too  difficult  for  an  instrument  of  less 
than  six  inches'  aperture. 

Clusters.  (1)  M.  39,  A.R.  21h  28m ;  Dec.  47°  54'  (about  3°  north  of  p ; 
p  itself  (fourth  mag.)  being  found  by  drawing  a  line  from  8  through 
a,  and  carrying  it  an  equal  distance  beyond.  (2)  $  VIII.  56,  A.R. 
20h  19m  ;  Dec.  40°  20'.  Beautiful  group,  ^°  north  and  a  little  east  of 
y.  The  bright  spots  in  the  Milky  Way  all  through  Cygnus  afford 
beautiful  fields  for  a  low  power. 

54.  Vulpecula  et  Anser  (Map  IV.).  —  This  little  constella- 
tion is  one  of  those  originated  by  Hevelius,  and  has  obtained 
more  general  recognition  among  astronomers  than  most  of  his 
creations.     It  lies  just  south  of  Cygnus,  and  is  bounded  to  the 
south  by  Delphinus,  Sagitta  and  Aquila. 

It  has  no  conspicuous  stars,  but  contains  one  very  interesting  tele- 
scopic object, —  the  "  Dumb-Bell  Nebula,"  — M.  27,  A.R.  19"  54m; 
Dec.  22°  23'.  On  a  line  from  y  Lyras  through  ft  Cygni,  produced  as  far 
again,  where  this  line  intersects  another  drawn  from  a  Aquilse  through 
y  Sagittse,  3^°  north  and  half  a  degree  east  of  the  latter  star. 

55.  Sagitta  (Map  IV.).  —  This  little  asterism,  though  very  incon- 
spicuous, is  one  of  the  old  48.     It  lies  south  of  Vulpecula,  and  the  two 
stars  a  and  ft,  which  mark  the  feather  of  the  arrow,  lie  nearly  midway 
between  ft  Cygni  and  Altair,  while  its  point  is  marked  by  y,  5°  farther 
east  and  north. 

Double  Stars.  (1)  £  (f°  N.W.  of  8,  the  middle  star  in  the  shaft  of 
the  arrow),  Mags.  5.5,  9;  Pos.  312°;  Dist.  8;'.6:  the  larger  star  is  itseli 
close  double,  distance  about  \",  making  an  interesting  triple  system. 

502 


§  56]  AQUILA.  37 

56.  Aquila  (Map  IV.). — This  constellation  lies  on  the  ce- 
lestial equator,  east  of   Ophiuchus  and  north  of   Sagittarius 
and  Capricornus.     It  is  bounded  on  the  east  by  Aquarius  and 
Delphinus,  and  on  the  north  by  Sagitta.     Its   characteristic 
configuration  is  that  formed  by  ALTAIR  (the  standard  first-mag- 
nitude star),  with  y  to  the  north  and  ft  to  the  south.     It  lies 
about  20°  south  of  (3  Cygni,  and  forms  a  fine  triangle  with 
Vega  and  a  Ophiuchi. 

Double  Star.  (1)  TT  Aquilse  (1^°  N.E.  of  y),  Mags.  6  and  7 ;  Pos. 
120°;  Dist.  1".5.  Good  test  for  3^-inch  glass. 

Cluster.  M.  11,  A.R.  18h  45m ;  Dec.  S.  6°  24'.  A  fine  fan-shaped 
group  of  stars  in  the  Milky  Way.  A  line  carried  from  Altair  through 
8  Aquilse  (see  map),  and  prolonged  once  and  a  half  as  far  again,  will 
find  it  about  4°  S.W.  of  A. 

The  southern  part  of  the  region  allotted  to  Aquila  on  our  maps  has 
been  assigned  to  Antinom.  This  constellation  was  recognized  by  some 
even  in  Ptolemy's  time ;  but  he  declined  to  adopt  it.  Hevelius  appro- 
priated the  eastern  portion  of  "Antinoiis"  for  his  constellation  of 
"  Scutum  Sobieski,"  and  M.  11  falls  just  within  its  limits. 

57.  Sagittarius  (Map  IV.).  — This,  the  tenth  of  the  zodia- 
cal constellations,  is  bounded  north  by  Aquila  and  Ophiuchus, 
west  by  Scorpio  and  Ophiuchus  (though  Bode  and  some  other 
authorities  crowd  in  a  piece  of  "  Telescopium  "  between  it  and 
Scorpio),  south  by  Corona  Australis,  Telescopium,  and  Indus, 
and  east  by  Microscopium  and  Capricornus.     It  contains  no 
stars  of  the  first  magnitude,  but  a  number  of  the  2-J-  and  third. 

The  most  characteristic  configuration  is  the  little  inverted 
"  milk  dipper "  formed  by  the  five  stars,  A,  <£,  o-,  T,  and  £,  of 
which  the  last  four  form  the  bowl,  while  A  (in  the  Milky  Way) 
is  the  handle.  8,  y,  and  e,  which  form  a  triangle  right-angled 
at  8,  lie  south  and  a  little  west  of  A,  the  whole  eight  together 
forming  a  very  striking  group.  There  is  a  curious  disregard 
of  any  apparent  principle  in  the  lettering  of  the  stars  of  this 
constellation  j  a  and  ft  are  stars  not  exceeding  in  brightness 

503 


38  UEANOGEAPHY.  [§  57 

the  fourth  magnitude,  about  4°  apart  on  a  north  and  south 
line  and  lying  some  15°  south  and  5°  east  of  £  (see  map). 
The  Milky  Way  in  Sagittarius  is  very  bright,  and  complicated 
in  structure,  full  of  knots  and  streamers,  and  dark  pockets. 

Names.  A,  Kaus  Borealis  ;  8,  Kaus  Media ;  e,  Kaus  A  ustralis ;  <j, 
Sddira.  This  star  is  strongly  suspected  of  irregular  variability. 

Double  Stars.  (1)  ju,1  (7°  N.W.  of  A;  on  the  line  from  £  through  <jj 
produced),  Triple;  Mags.  A  3.5,  B  9.5,  C  10;  A-B,  Pos.  315°,  Dist. 
40";  A-C,  Pos.  114°,  Dist.  45". 

Clusters  and  Nebulce.  (1)  M.  22,  A.R.  18h  29m ;  Dec.  S.  24°  0'  (3° 
X.W.  of  A,  and  midway  between  ju,  and  cr).  Capital  object  for  a  4-inch 
telescope.  (2)  M.  25,  A.R.  18"  25ni;  Dec.  S.  19°  10'  (7°  north  and  1° 
east  of  A;  visible  to  naked  eye).  (3)  M.  8;  A.R.  17h  57m;  Dec.  S. 
24°  21'  (a  little  south  of  the  line  <f>\  produced,  and  as  far  from  A  as 
A  from  <£;  also  visible  to  naked  eye).  (4)  $  IV.  41,  The  Trifid 
Nebula,  A.R.  17h  55™  ;  Dec.  S.  23°  2'  (I1,0  north  of  M.  8,  and  almost 
exactly  on  the  line  <£A  produced).  A  very  beautiful  and  interesting 
object. 

58.  Capricornus  (Map  IV.). — This,  the  eleventh  of  the 
zodiacal  constellations,  follows  Sagittarius  on  the  east.  It  has 
Aquarius  and  Aquila  (Antinous)  on  the  north,  Microscopium 
and  Piscis  Austrinus  on  the  south,  and  Aquarius  on  the  east. 
It  has  110  bright  stars,  but  the  configuration  formed  by  the 
two  a's  (ax  and  a2)  with  each  other  and  with  ft  3°  south,  is 
characteristic  and  not  easily  mistaken  for  anything  else.  The 
two  a's,  a  pretty  "  double "  to  the  naked  eye,  lie  on  the  line 
from  ft  Cygni  (at  the  foot  of  the  cross)  through  Altair,  pro- 
duced about  25°.  On  the  line  aft  about  3°  distant,  lies  p  (of 
the  fourth  magnitude),  with  two  other  small  stars  near  it. 
From  this  a  line  20°  long,  carried  due  east  through  9  and  i  (of  the 
fourth  magnitude),  brings  the  eye  to  y  and  8  of  the  third,  the 
latter  marking  the  constellation's  eastern  limit. 

Names,     a,  Algiedi  (prima  and  secundd)  ;  8,  Deneb  Algiedi. 
Double  Stars.      (1)  ax  and  a.2  (pretty  with  a  very  low  power),  Mags. 
3  and  4 ;  Dist.  6'  13".     a%  has  also  a  very  faint  companion,  invisible 


§  58]  DELPHINUS.  39 

with  any  telescope  of  less  than  6-inch  aperture  ;  Pos.  150°;  Dist.  7".5, 
The  companion  is  itself  double;  Dist.  about  1";  Pos.  240°.  (2)  ft, 
Mags.  3.5,  7  ;  Pos.  267° ;  Dist.  3'  25".  The  companion  is  also  a  close 
and  difficult  double.  (3)  p  (the  northern  star  in  the  little  triangle  it 
forms  with  TT  and  o),  Mags.  5,  9;  Pos.  177°;  Dist.  3".8.  (4)  TT  (the 
S.W.  one  in  the  same  triangle),  Mags.  5,  9  ;  Pos.  146°;  Dist.  3".5. 

Nebula.  M.  30,  A.R.  21h  34™  ;  Dec.  S.  23°  42'  (about  1°  west  and 
a  little  north  of  41  Capricorn!,  a  fifth-magnitude  star,  7°  south  of  y 
Capricorn!). 

59.  Delphinus  (Map  IV.). — This  little  asterism  is  ancient, 
and  unmistakably  characterized  by  the  rhombus  of  third-mag- 
nitude stars  known  as  "  Job's  Coffin."     It  lies  about  15°  north- 
east of  Altair,  bounded  north  by  Vulpecula  and  west  by  Aquila. 
There  are  a  few  stars  visible  to  the  naked  eye  in  addition  to 
the  four  that  form  the  rhombus.     Epsilon,  about  3°  southwest. 
\s  the  only  conspicuous  one. 

Names,  a,  Svalocin;  ft,  Rotanev.  These  were  given  in  joke  by 
Nicolaus  Cacciatore,  a  Sicilian  astronomer,  about  1800.  The  letters 
of  the  two  names  reversed  make  Nicolavs  Venator;  Venator  being  the 
translation  of  the  Italian  "  Cacciatore,"  which  means  "  Hunter."  The 
joke  is  good  enough  to  keep. 

Double  Stars.  (1)  y  (at  the  N.E.  angle  of  the  rhombus),  Mags.  4, 
7;  Pos.  271°;  Dist.  11".3.  (2)  ft,  a  very  close  and  rapid  binary, 
beyond  the  reach  of  all  but  large  telescopes.  It  has,  however,  two 
little  companions,  distant  about  30". 

60.  EquuleilS    (Map    IV.).  —  This    little    constellation    is    still 
smaller  than  the  Dolphin,  and  contains  no  such  characteristic  star 
group.     It  lies  about  20°  due  east  of  Altair,  and  10°  S.E.  of  Delphinus 
(see  map). 

Double  Stars.  (1)  e,  Mags.  5,  7.5;  Pos.  73°;  Dist.  11".  The  larger 
star  is  also  close  double  ;  Mags.  5.5.  and  7 ;  Pos.  290°;  Dist.  0".9.  Per- 
haps resolvable  with  a  4-inch  telescope. 

61.  Lacerta  (Maps  I.  and  IV.).  —  This  is  one  of  Hevelius's  mod- 
ern constellations,  lying  between  Cygnus  and  Andromeda,  with  no 
stars  above  the  4^  magnitude.     It  contains  a  few  telescopic  objects, 
but  nothing  suited  to  our  purpose. 

505 


40  URANOGRAPHY.  [§  62 

62.  P6g&sus  (not   Pegas'us)    (Map   IV.).  —  This  covers  an 
immense  space  which  is  bounded  on  the  north  by  Andromeda 
and  Lacerta,  on  the  west  by  Cygnus,  Vulpecula,  Delphinus, 
and  Equuleus,  on  the  south  by  Aquarius  and  Pisces,  and  on 
the  east  by  Pisces  and  Andromeda.     Its  most  notable  config- 
uration is  "  the  great  square/7  formed  by  the  second-magnitude 
stars  a,  ft  and  y  Pegasi,  in  connection  with  a  Andromedse 
(sometimes  lettered  8  Pegasi)  at  its  northeast  corner.     The 
stars  of  the  square  lie  in  the  body  of  the  horse,  which  has  no 
hindquarters.     The  line  drawn  from  a  Andromedse   through 
a  Pegasi,  and  produced  about  an  equal  distance,  passes  through 
£  and  £  in  the  animal's  neck,  and  reaches  0  (third  magnitude) 
in  his  ear.     Epsilon,  8°  northwest  of  0,  marks  his  nose.     The 
forelegs  are  in  the  northwestern  part  of  the  constellation  just 
east  of  Cygnus,  and  are  marked,  one  of  them  by  the  stars  ^ 
and  TT,  the  other  by  t  and  K. 

Names,     a,  Markab  ;  ft  Scheat;  y,  Algenib ;  e,  Enif. 

Double  Star.  K,  Mags.  4,  11 ;  Pos.  302°;  Dist.  12".  The  large  star 
is  also  itself  an  extremely  close  double;  Dist.  0".3;  (pointed  at  by 
the  northern  edge  of  the  "  square,"  at  a  distance  one  and  a  quarter 
times  its  length.) 

Cluster.  M.  15,  A.R.  21h  24m;  Dec.  11°  38'  (on  the  line  from  0 
through  e,  produced  half  its  length,  and  just  west  of  a  sixth-magni- 
tude star). 

63.  Aquarius   (Map  IV.). — This,  the  twelfth  and  last  of 
the  zodiacal  constellations,   extends  more  than   3^  hours   in 
right   ascension,    covering   a   considerable    region    which    by 
rights  ought  to  belong  to  Capricornus.     It  is  bounded  north 
by  Delphinus,  Equuleus,  Pegasus,  and  Pisces ;  west  by  Aquila 
and  Capricornus ;  south  by  Capricornus  and  Piscis  Austiinus, 
and  east  by   Cetus.     The  most  notable   configuration   is  the 
little  Y  of  third  and  fourth  magnitude  stars  which  marks  the 
"water   jar"   from   which   Aquarius   pours   the    stream  that 
meanders   down   to   the  southeast  and  south   for  30°,  till  it 

606 


§  63]  PISCIS   AUSTRINUS.  41 

reaches  the  Southern  Fish.  The  middle  of  the  Y  is  about  18° 
south  and  west  of  a  Pegasi,  and  lies  almost  exactly  on  the 
celestial  equator.  A  line  drawn  west  and  a  little  south  from 
y  (the  westernmost  star  of  the  Y)  to  a  Capricorni,  passes 
through  (3  (third  magnitude)  at  one-third  of  the  way,  and 
through  /A  and  e  (fourth  and  3J)  two-thirds  of  the  way.  a 
(third  magnitude)  lies  4°  west  and  a  little  north  of  y.  8  (third 
magnitude)  lies  about  half-way  between  the  Y  and  Fomalhaut 
in  the  Southern  Fish,  3°  or  4°  east  of  the  line  that  joins  them. 

Names,     a,  Saad  el  Melik  ;  J3,  Saad'el  Sund ;  8,  Skat. 

Double  Stars.  (1)  £  (the  central  star  of  the  Y),  Mags.  4,  4.5;  Pos, 
332° ;  Dist.  3".6  ;  pretty  and  easy.  (2)  12  Aquarii  (7°  due  west  of  /:?, 
and  the  brightest  star  in  the  vicinity),  Mags.  5.5,  8.5;  Pos.  190°;  Dist. 
2". 8;  yellowish  white  and  light  blue. 

Cluster*  and  Nebulce.  (1)  M.  2;  A.R.  21"  17"' ;  Dec.  S.  1°  22'  (on 
the  line  drawn  from  £  through  a,  produced  one  and  a  quarter  times  its 
own  length).  (2)  II  IV.  1,  A.R.  20'1  58m ;  Dec.  8.  11°  50'  (nearly  on 
the  line  from  a  through  /3,  produced  its  own  length,  and  1£°  west  of 
v ;  fifth  magnitude) ;  planetary  nebula,  bright  and  vividly  green. 

64.  Piscis  Austrinus  (or  Australis)  (Map  IV.). — This  small 
constellation,  lying  south  of  Aquarius  and  Capricornus,  pre- 
sents little  of  interest.  It  has  one  bright  star,  FOMALHAUT 
(pronounced  Fomalhawt),  of  the  1^  magnitude,  which  is  easily 
recognized  from  its  being  nearly  on  the  same  hour-circle  with 
the  western  edge  of  the  great  square  of  Pegasus,  45°  to  the 
south  of  a,  and  solitary,  having  no  star  exceeding  the  fourth 
magnitude  within  15°  or  20°.  It  contains  no  telescopic  objects 
available  for  our  purpose. 

South  of  it,  barely  rising  above  the  southern  horizon,  lie  the  con- 
stellations of  Microscopium  and  Grus.  The  former  is  of  no  account. 
The  latter  is  a  conspicuous  constellation  in  the  southern  hemisphere, 
and  its  two  brightest  stars,  a  and  /3,  of  the  second  magnitude,  rise 
high  enough  to  be  seen  in  latitudes  south  of  Washington.  They  lie 
about  20°  south  and  west  of  Fomalhaut. 

607 


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/        ARA 

THE  ELEMENTS  OF  GEOLOGY 

By  WILLIAM  HARMON  NORTON 
Professor  of  Geology  in  Cornell  College,  Mt.  Vernon,  Iowa 


8vo.      Cloth.      461  pages.      Illustrated.      List  price,  $1.40  ;   mailing  price,  $1.55 

THE  essentials  of  the  science  of  geology  are  treated 
with  fullness  and  ample  illustration  in  this  text-book 
for  beginners.  By  limiting  his  discussion  chiefly  to  this 
continent  the  author  has  been  able  to  devote  a  large 
amount  of  space  to  the  principles  which  he  describes.  The 
following  characteristics  are  important. 

1.  The  outline  is  exceptionally  simple.    Under  the  leading  geological 
processes  are  grouped   the  rock  structures  and  land  forms  of  which 
they  are  the  cause. 

2.  The    inductive    method    is    emphasized    throughout.      Concrete 
examples  are  given  large  space  as  the  basis  of  generalizations  of  the 
science.     Numerous  exercises  and  problems,  many  of  which  are  in  the 
form  of   diagrams,  are   designed    to    train  the   pupil  and   to  test  his 
knowledge. 

3.  The  cycle  idea  is  made  prominent,  and  both  the  records  of  erosion 
and  those  of  sedimentation  are  given  special  attention. 

4.  In  historical  geology  a  broad  view  is  afforded  of  the  development 
of  the  North  American  continent  and  of  the  evolution  of  life  upon  the 
earth.     Only  the  leading  types  of  plants  and  animals  are  mentioned, 
and  special  attention  is  given  to  those  which  mark  the  lines  of  descent 
of  forms  now  living. 

The  book  is  designed  for  use  in  high  schools  and  acad- 
emies, and  may  also  be  found  useful  in  short  elementary 
college  courses. 


GINN   &  COMPANY   PUBLISHERS 


ELECTRICITY,  SOUND,  AND 
LIGHT 

By  ROBERT  ANDREWS  MILLIKAN,  Associate  Professor  of  Physics  in 
The   University  of  Chicago,   and  JOHN   MILLS,    Instruc- 
tor in  Physics  in  Western  Reserve  University 


8vo.    Cloth.     389  pages.    Illustrated.    List  price,  $2.00;  mailing  price,  $2. 15 


THIS  book  represents  a  one-semester  college  course 
which  has  been  given  in  substantially  its  present  form 
for  a  number  of  years  in  The  University  of  Chicago,  Western 
Reserve  University,  and  several  other  similar  institutions. 

It  is  the  outgrowth  of  the  conviction  that  in  courses  of 
intermediate  grade  in  colleges,  universities,  and  engineering 
schools,  a  thorough  grasp  of  the  fundamental  principles  of 
physics  is  not  readily  gained  unless  theory  is  presented 
in  immediate  connection  with  related  concrete  laboratory 
problems.  It  represents  a  complete  logical  development, 
from  the  standpoint  of  theory  as  well  as  experiment,  of  the 
subjects  indicated  in  the  title. 

The  book  contains  twenty-eight  chapters,  —  sixteen  in 
electricity,  five  in  sound,  and  seven  in  light.  Each  chapter 
is  concluded  by  the  appropriate  experiment.  These  experi- 
ments have  been  put  into  such  form  that  they  demand  no 
special  apparatus  and  can  be  performed  by  students  in  the 
second  year  of  college  within  the  limited  time  of  a  two-hour 
laboratory  period.  " Electricity,  Sound,  and  Light"  may  be 
combined  with  " Mechanics,  Molecular  Physics,  and  Heat," 
by  Professor  Millikan,  to  form  the  texts  for  an  excellent 
course  of  one  year  in  college  physics. 


GINN   AND   COMPANY   PUBLISHERS 


YOUNG'S 

MANUAL  OF  ASTRONOMY  AND 
GENERAL  ASTRONOMY 

PROFESSOR  YOUNG'S  position  among  the  great  astron- 
omers of  the  world  is  firmly  established.     As  a  clear  and 
forcible  writer  he  is  equally  well  known.     His  series  of 
astronomical  text-books  combines  in  an  unusual  degree  the  qual- 
ities of  accurate  scholarship,  simplicity  of  style,  and  clearness  of 
statement  which  belong  to  every  successful  text- book. 


MANUAL  OF  ASTRONOMY 

By  CHARLES  A.  YOUNG,  Professor  of  Astronomy  in  Princeton  University.    8vo.     Half 
leather.     611  pages.     Illustrated.     List  price,  $2.25  ;  mailing  price,  $2.45. 

Young's  "Manual  of  Astronomy"  is  a  new  work  prepared  in  response 
to  a  pressing  demand  from  various  quarters  for  a  class-room  text-book 
intermediate  between  the  author's  "General  Astronomy"  and  his 
"  Elements  of  Astronomy." 

The  subject-matter  of  the  book  has  been  derived  largely  from  its 
predecessors,  but  everything  has  been  carefully  worked  over,  rearranged, 
rewritten  where  necessary,  and  added  to  in  order  to  adapt  it  thoroughly 
to  the  end  in  view  and  to  harmonize  it  with  the  latest  astronomical 
research. 

The  unusually  numerous  illustrations  are  particularly  noteworthy, 
both  for  their  artistic  excellence  and  for  their  value  in  explaining  the 
text.  Among  them  are  a  number  of  important  photographs  which  have 
never  before  been  inserted  in  a  text-book.  The  mechanical  execution 
of  the  book  as  a  whole  is  above  criticism,  and  has  called  forth  the 
enthusiastic  praise  of  the  general  reader,  the  scientist,  and  the  teacher. 

GENERAL  ASTRONOMY 

By  CHARLES  A.  YOUNG,  Professor  of  Astronomy  in  Princeton  University.     8vo.     Half 
morocco.     630  pages.     Illustrated.     List  price,  $2.75  ;  mailing  price,  $3.00. 

This  text-book  is  intended  for  a  general  course  in  colleges  and  schools 
of  science,  and  requires  only  an  elementary  knowledge  of  algebra, 
geometry,  and  trigonometry.  It  has  been  found  an  eminently  satisfactory 
book  for  this  grade  of  work. 


GINN    &    COMPANY    PUBLISHERS 


TEXT-BOOKS  ON   ASTRONOMY 

By  CHARLES  A.   YOUNG 
Late  Professor  of  Astronomy  in  Princeton  University 

LESSONS  IN  ASTRONOMY.  (Revised  Edition.)  Including  Star  Maps. 
420  pages.  Illustrated.  List  price,  $1.25  ;  mailing  price,  $1.40. 

ELEMENTS    OF   ASTRONOMY.     With   a  Uranography.     464  +  42    pages 

and  four  double-page  star  maps.     List  price,  $1.60  ;  mailing  price,  #1.75. 

URANOGRAPHY.     From  the  "  Elements  of  Astronomy."     Flexible  covers.     42  pages 

and  four  double-page  star  maps.     List  price,  30  cents ;  mailing  price,  35  cents. 

MANUAL  OF  ASTRONOMY.  611  pages.  Illustrated.  List  price,  $2.25  ; 
mailing  price,  $2.45. 

GENERAL  ASTRONOMY.  A  text-book  for  colleges  and  scientific  schools. 
630  pages.  Illustrated  with  250  cuts  and  diagrams  and  supplemented  with 
the  necessary  tables.  List  price,  $2.75  ;  mailing  price,  $3.00. 

A  SERIES  of  text-books  on  astronomy  for  higher  schools, 
academies,  and  colleges,  prepared  by  one  of  the  most  dis- 
tinguished astronomers  of  the  world,  a  popular  lecturer  and 
a  successful  teacher. 

The  "Lessons  in  Astronomy"  was  prepared  for  schools  that 
desire  a  brief  course  free  from  mathematics.  The  book  is  fully 
down  to  date,  and  several  beautiful  plates  of  astronomical  objects 
and  instruments  have  been  inserted  in  the  revised  edition. 

The  "  Elements  of  Astronomy "  is  a  text-book  for  advanced 
high  schools,  seminaries,  and  brief  courses  in  colleges  generally. 
Special  attention  has  been  paid  to  making  all  statements  accurate. 

The  "  Manual  of  Astronomy  "  is  a  new  work  prepared  in  response 
to  a  pressing  demand  for  a  class-room  text-book  intermediate  be- 
tween the  author's  "  General  Astronomy  "  and  his  "  Elements  of 
Astronomy."  It  is  largely  made  up  of  material  drawn  from  the 
earlier  books,  but  rearranged,  rewritten  when  necessary,  and  added 
to  in  order  to  suit  it  to  its  purpose  and  to  bring  it  thoroughly 
down  to  date. 

The  eminence  of  Professor  Young  as  an  original  investigator  in 
astronomy,  a  lecturer  and  writer  on  the  subject,  and  an  instructor 
in  college  classes,  led  the  publishers  to  present  the  "  General 
Astronomy  "  with  the  highest  confidence  ;  and  this  confidence  has 
been  fully  justified  by  the"  event.  It  is  conceded  to  be  the  best 
astronomical  text-book  of  its  grade. 


GINN  &  COMPANY  PUBLISHERS 


A 


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BERKELEY 

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